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IntroductionIn electronics, transient voltage suppressor (TVS) diodes are components that protect sensitive circuitry from being damaged due to high voltage transients. Because tvs diodes are constructed with large cross sectional area junctions for absorbing high transient currents. The primary source of high voltage transients are electrostatic discharge, electrical fast transient, and surge events. This notes will tell you how does a tvs diode work to prevent a circuit malfunction and protect devices.CatalogIntroductionⅠ Transient Voltage Suppressors (TVS)1.1 What Transient Means??1.2 What Causes a Circuit to Be Transient?1.3 What Does a TVS Do?1.4 What Can Be A Transient Voltage Suppressor?Ⅱ Transient Voltage Suppression Diode2.1 TVS Diode Overview2.2 How To Choose A TVS Diode?Ⅲ How Do You Use TVS Diode for Circuit Protection3.1 TVS Diode in Circuits3.2 Major TVS Diode ParametersⅣ ConclusionⅠ Transient Voltage Suppressors (TVS)1.1 What Transient Means?Transients are spikes of short duration in voltage or current that can in several ways damage a circuit. Some transients only occur once, and some of them may be repetitive. These transients vary from a few millivolts to thousands of volts and can last for hundreds of milliseconds to nanoseconds. Due to inductive load switching or defective contacts in switches and connectors, transients may be produced internally. It can be produced externally because of lightning strikes or inductive switching.1.2 What Causes Transient Voltage?Transient voltages are caused by the sudden release of stored energy due to incidents such as lightning strikes, unfiltered electrical equipment, contact bounce, arcing, capacitor bank or generators being switched ON and OFF. Transient voltages differ from swells by being larger in magnitude and shorter in duration. Transient voltages typically last from less than a microsecond to several milliseconds. Transient voltages are generally classified into two different types depending on where they occur on a power system: normal mode or common mode.1.3 What Does a TVS Do?Transient voltage suppressors or TVS are devices of protection used to save the circuits from this unexpected voltage or current spike. Positioning these TVS devices in parallel with the circuit is the primary way to protect a circuit from overvoltage.1.4 What Can Be A Transient Voltage Suppressor?Metal oxide varistor, TVS diode, Zener diode or bypass capacitor are several types of TVS devices that can be used for transient voltage suppression diodes.Transient Voltage Suppressors can be divided into two types, clamping and crowbar. Clamping devices restrict the voltage to a level which is fixed. They consume the excess energy of the overvoltage event in doing so. An instance of clamping devices is TVS diodes.On the other hand, once activated, Crowbar devices effectively shorten the protected line, redirecting the excess energy away from the protected circuit. As you can see in the graph below, when a trigger voltage (spike) is detected, the crowbar device shorts the circuits such that the line voltage is decreased, then the line voltage rises again to a stable state for regular circuit operation after some time as the crowbar device delays the circuit.Transient Voltage Suppression Diode SymbolⅡ Transient Voltage Suppression Diode2.1 TVS Diode OverviewThe transient voltage suppression diode ((ESD protection diode)) is a solid-state PN-Junction diode explicitly designed to remove the sudden or momentary effects of overvoltage on sensitive semiconductors and circuits. TVS diode is a clamping system, so it absorbs the excess energy of the overvoltage event if the induced voltage reaches the avalanche breakdown voltage, and then automatically resets after overvoltage situation. Although it is true that standard diodes and Zener diodes can also be used for overvoltage/transient safety, since standard and Zener diodes are designed for rectification and voltage control, they are not as robust as transient voltage suppressor diodes.How Does Transient Voltage Suppressor Diode Work?2.2 How To Choose A TVS Diode?When selecting a suitable transient suppressor, it is necessary what types tvs diode have? Like every other avalanche diode, a unidirectional transient voltage suppressor diode acts in the forward direction as a rectifier in a circuit, and this unidirectional diode is made to withstand very high peak currents. The unidirectional TVS diode symbol is seen in the picture below, and it's almost like a Zener diode.On the other hand, two mutually opposing avalanche diodes connected in series with each other can represent a bidirectional transient-voltage-suppression diode. In parallel with the system or circuit to be secured, these diodes are connected. These diodes are produced as a single element, unlike the symbol. The Bidirectional TVS Diode symbol is shown in the picture below.Introduction to Transient Voltage Suppressors (TVS) CharacteristicBefore take a tvs diode in circuit, it is critical to specify the peak impulse capability for a given transient waveform. In most diodes, the peak pulse capability will be rated either 8/20µs or 10/1000µs impulse waveform. It is possible to classify Transient Voltage Suppressor Diodes into two groups. One of them is unidirectional, and the other is bidirectional.Ⅲ How Do You Use TVS Diode for Circuit Protection3.1 TVS Diode in CircuitsIn parallel with the system or circuit to be secured, TVS diodes are attached. The TVS system is specifically designed to break down at a particular voltage level and, without sustaining damage, conduct large quantities of current.The TVS diode appears as an open circuit under normal voltage conditions, but a low leakage current is present. The TVS diode junction avalanches when the usual voltage reaches a certain amount and overvoltage is redirected from the safe circuit as a result and shunted through the TVS diode. When the overvoltage goes down, the system automatically resets.In addition, the VI characteristic curve of the tvs diode is similar to that of a Zener diode, TVS diodes are specifically designed, characterized, and tested for transient voltage suppression. By contrast, zener diodes are designed and specified for voltage regulation.3.2 Major TVS Diode ParametersMany types of TVS diodes, equipped for a particular application, are on the market. When selecting a TVS diode to protect an external interface, there are a couple of key parameters you want to pay special attention to. Here is the following parameters in the datasheet to help you find a right TVS diode.Reverse Stand-Off Voltage (VR)The highest voltage that can be applied to the protector without the system actually being triggered is the reverse stand-off voltage. The VR of the system should be equal to, or greater than, the peak operating voltage of the safe circuit. This is to ensure that the regular circuit operation or signal voltage is not clipped by the safety system.Breakdown voltage (VBR)The voltage at which the diode can begin to protect and conduct current is the breakdown voltage. The VBR is usually defined at 1mA.Clamping Voltage (VC)The clamping voltage is the maximum voltage that will be exposed to the safe circuit during the event of the test waveform. The clamping voltage for a 1A or 2A waveform that has an 8μS rise time is given on most datasheets.Peak Pulse Current (IPP)The highest current which the safety system can withstand is the peak pulse current.Ⅳ ConclusionThe TVS diode is commonly used in low-energy circuits and systems for diversion/clamping, and in circuits for ESD safety. Because one advantage of using external TVS diodes is that they typically provide level four IEC ESD protection. Under normal operating conditions, the TVS diode presents a high impedance to the protected circuit. Ideally, the device appears as an open circuit, although a small amout of leakage current is present. TVS diode applications can be found in data and signal lines, memory for microprocessors and MOS, power lines for AC/DC, and telecommunication equipment. Frequently Asked Questions about TVS Diodes1. What is Transient-voltage-suppression diode?A transient-voltage-suppression (TVS) diode, also transil or thyrector, is an electronic component used to protect electronics from voltage spikes. In other words, transient voltage suppressor diodes are very popular devices used to instantaneously clamp transient voltages (e.g., ESD events) to safe levels. 2. How does a transient voltage suppressor diode work?Transient Voltage Suppressor Diode is a clamping device, so whenever the induced voltage exceeds the avalanche breakdown voltage, it absorbs the excess energy of the overvoltage event, and then it automatically resets after overvoltage condition. 3. What does a transient voltage suppressor do?Transient Voltage Suppressors (TVS) are devices used to protect vulnerable circuits from electrical overstress such as that caused by electrostatic discharge, inductive load switching and induced lightning. 4. What does a suppression diode do?A transient-voltage-suppression (TVS) diode, also transil or thyrector, is an electronic component used to protect electronics from voltage spikes induced on connected wires.
kynix On 2021-01-18
Warm hints: The word in this article is about 5400 words and reading time is about 25 minutes This article is equal to a comprehensive course about automobile sensors which including the basic introduction of automobile sensors, their types, applications, functions, and market analysis, etc. Electronic technology has become the leading factor in the direction of the development of a new generation of automobiles, and sensors are the core components of electronic technology. More and more modern cars have used sensors more and more, in order to improve the economic, dynamic and emission performance of automobile engines, improve the braking performance, steering performance and safety performance of the vehicle. The key to achieve these goals lies in the electronic and intelligent vehicle, the prerequisite is the timely acquisition of all kinds of information, which is bound to require a large number of sensors in the car. Catalogs I. An Overview of Automobile Sensors II. The Development History of Automobile Sensors III. Types of Automobile Sensors and Their Functions IV. Sensors Used in Automobile Engines and Their Functions 4.1 Automobile Temperature Sensor 4.2 Automobile Pressure Sensor 4.3 Air Flow Sensor 4.4 Fuel Flow Sensor 4.5 Engine Speed Sensor 4.6 Gas Concentration Sensor-oxygen Sensor V. Application of Vehicle Sensor in Vehicle Chassis Electronic Control System VI. Sensor Application in Automobile Safety System VII. Other Major Automotive Sensors VIII. Automotive Sensors Market Size--Its Market Trend FAQ I. An Overview of Automobile Sensors The automobile sensor is the input device of the automobile computer system. It takes all kinds of working condition information in the car, such as speed, temperature of various medium, engine operation condition and so on, and convert it into the device or device that can be input signal according to certain law. Simply speaking, the sensor transfers the non electric quantity to the electrical signal to transmit to the ECU, so that the car is in the best working state. An Overview of Automobile Sensors In modern automotive electronic control, sensors are widely used in various systems of engine, chassis, and body. Automobile sensors are responsible for the acquisition and transmission of information in these systems. The information collected by the sensors is processed by the computer (electronic control unit), and the instructions sent to the actuator are formed to complete the electronic control. The sensor is a very important device in the electronic control and self-diagnosis system. It can identify the changes in the outside world and the changes of the system itself in time and then control the work of the system itself according to the information of the change. Each system control process relies on sensors to feedback information and achieves automatic control. Automotive sensors usually consist of three parts: sensing element, converting element, and measuring circuit. (1)the sensitive element is the part that can be measured directly (or response), and is about to be converted into a non electric or other quantity that is determined to be determined by the sensing element of the sensor. (2)the conversion element converts the above non electric quantity into electrical parameters. (3)The function of the measurement circuit is to convert the electrical parameters input by the conversion element to the measurable quantity of voltage, current, or frequency, in order to display, record, control and handle the parts. Measurement circuit The sensor is at the interface between the research object and the test system, namely the first of detection and control. The sensor is a window to perceive, obtain and detect information. All the information obtained in the process of scientific research and automated production must be obtained by the sensor and converted into an easy transmission and processing electrical signal. Its role and status are particularly important. The following figure is the list of correspondence between the human body and machine, which helps us further understand its function. In modern automotive electronic control, sensors are widely used in various systems of engine, chassis, and body. The vehicle sensors are responsible for the acquisition and transmission of information in these systems. The computer (electronic control unit ECU) sends out instructions to the actuator after the signal is processed in a hurry, and the electronic control is implemented. The sensor is a very important device in the electronic control and self-diagnosis system. It can identify the changes in the outside world and the changes of the system itself in time and then control the work of the system according to the information of the change. Each system control process relies on sensors to feedback information and achieves automatic control. II. The Development History of Automobile Sensors In the 1960s, there were only oil pressure sensors, oil sensors, and water temperature sensors on cars. They were connected with meters or indicator lights. After the 1970s, in order to control emissions, a number of sensors were added to help control the vehicle's power system, as the catalytic converters, electronic ignition, and fuel injection devices needed to maintain a certain air-fuel ratio to control emissions during the same period. Until the 1980s, ABS and airbags improved vehicle safety. The Development History of Automobile Sensors Sensors are used today to determine the temperature and pressure of various fluids, such as intake temperature, air inlet pressure, cooling water temperature, and fuel injection pressure, and sensors used to determine the speed and position of various parts (such as speed, throttle opening, camshaft, crankshaft, angle and speed of the transmission, the position of the exhaust recirculation valve (EGR), etc.); and for measurement. Sensors for engine load, detonation, broken fire, and oxygen content in exhaust gas; sensors to determine the seat position; sensors to determine wheel speed, road elevation difference, and tire pressure in the anti-lock braking system and suspension control device; and to protect the airbags of the front occupants, not only need more collision sensors and acceleration sensors. The researchers also use the anti-collision sensors (ranging radar or other ranging sensors) to determine and control the lateral acceleration of the car, the instantaneous speed of each wheel and the required torque, so that the braking system is a part of the vehicle stability control system. III. Types of Automobile Sensors and Their Functions (1)According to the relationship of energy, sensors can be classified into two types: active and passive based on their energy relations. Most of the sensors used in cars belong to passive sensors, which require additional input power to produce electrical signals, so the sensor is actually an energy controller. (2)According to the classification of signal conversion according to the signal conversion classification, it can be divided into one kind of non electricity conversion into another kind of non electricity, such as elastic sensitive element and pneumatic sensor; the other is the transducer converted from non electricity to electricity, such as thermocouple temperature sensor, piezoelectric accelerometer and so on. (3)Classification according to input quantity according to input quantity is classified according to the measurement, which can be divided into displacement, velocity, acceleration, angular displacement, angular velocity, force, torque, pressure, vacuum degree, temperature, current, gas composition, concentration sensor and so on. For example, the following air flow sensor: Air flow sensor (4)According to the working principle classification according to the working principle of the sensor, there are resistance, capacitance, strain, inductance, photoelectric, photosensitive, piezoelectric, thermoelectric sensor, etc. (5)According to the output signal classification, according to the sensor output signal, there are analog and digital sensors. Simulation system adoption and digital system adoption IV. Sensors Used in Automobile Engines and Their Functions Electronic control of engines has been considered to be one of the main technology fields of automobiles. The sensor of engine control system is the core of the whole automobile sensor, and there are many kinds, including temperature sensor, pressure sensor, position and speed sensor, flow sensor, gas concentration sensor and detonation sensor, etc. These sensors provide the engine's work condition information to the engine's electronic control unit for accurate control of the engine working condition, in order to improve engine power, reduce fuel consumption, reduce exhaust emissions and perform fault detection. Sensors Used in Automatic Inductive Door 4.1 Automobile Temperature Sensor Temperature sensor like automobile temperature sensor is mainly used to detect engine temperature, suction gas temperature, cooling water temperature, fuel temperature, and catalytic temperature. Water temperature state indicatior The temperature sensor has three main types: thermistor, wire wound resistor, and thermal couple resistor. These three types of sensors have their own characteristics, and their applications are also slightly different. The thermistor temperature sensor has high sensitivity and good response characteristics, but it has poor linearity and low temperature. Among them, the universal temperature range is -50 C to 30 C, the precision is 1.5%, the response time is 10ms, the high-temperature type is 600 to 1000, the precision is 5%, the response time is 10ms; the precision of the wire-wound resistance temperature sensor is high, but the response characteristic is poor; the precision of the thermocouple resistance temperature sensor is high and the temperature range is wide, but it needs to be used together with the amplifier and cold end treatment. Other practical products have ferric oxygen sensor (temperature range from -40 to 120, 2%), metal or semiconductor membrane air temperature sensor (temperature range from -40 to 150, 2%, 5%, response time 20ms). 4.2 Automobile Pressure Sensor The pressure sensor is the most used sensor in automobiles. It is mainly used to detect air pressure of airbags, the fluid pressure of transmission system, injection pressure, engine oil pressure, inlet pipe pressure, the fluid pressure of air filtration system, and so on. At present, the more commonly used vehicle pressure sensors are capacitive, piezoresistive, differential transformer, and surface acoustic wave. The capacitive pressure sensor is mainly used to detect negative pressure, hydraulic pressure, and air pressure. The measurement range is 20kPa to 100kPa. Its characteristics are high input energy, good dynamic response characteristics, and good environmental adaptability. The performance of the piezoresistive pressure sensor is affected by temperature, and it needs another temperature compensation circuit, but it is suitable for mass production; the differential transformer type pressure sensor has a large loss. The acoustic surface wave pressure sensor has the characteristics of small volume, lightweight, low power, low power, high reliability, high sensitivity, high resolution, and digital output. It can be used in the pressure detection of the automobile air suction valve and can work steadily at high temperatures. 4.3 Air Flow Sensor The flow sensor is mainly used for measuring the airflow and fuel flow of the engine. The intake volume is one of the basic parameters for fuel injection calculation. The Mass Air Flow Sensor (MAF) is a computer-controlled sensor that calculates the volume and density of the air taken in by the engine. This in turn ensures the right amount of fuel is used for optimized operating conditions. If this sensor is faulty, the car may stall and the fuel usage will be higher than necessary. The function of the airflow sensor is to perceive the size of the airflow and transform it into an electrical signal to transmit to the electronic control unit of the engine. The measurement of airflow is used in the engine control system to determine combustion conditions, control air-fuel ratio, start, and ignition. There are 4 types of airflow sensors: rotary wing, Carmen vortex, hot wire, and hot film. The main technical indicators of the airflow sensor are: the working range is 0.11m3/min to 103m3/min, the working temperature is -40 to 120 degrees, and the accuracy is more than 1%. 4.4 Fuel Flow Sensor The fuel flow sensor is used to detect the flow rate of fuel, mainly with a water wheel and circulating ball. The dynamic range is 0 ~ 60kg/h, the working temperature is -40 to 120, the precision is 1%, and the response time is < 10ms. The position and speed sensor of position and speed sensor crankshaft and speed sensor is mainly used to detect engine crankshaft angle, engine speed, throttle opening, speed, and so on. It provides a reference point signal for ignition time and injection time and provides an engine speed signal at the same time. 4.5 Engine Speed Sensor Engine Speed Sensor is attached to the crankshaft and monitors the spinning speed of the crankshaft, which controls the fuel injection and timing of the engine. Electromagnetic crankshaft position sensor At present, the position and speed sensors used in automobile are mainly AC generator type, magnetoresistance type, Holzer effect type, reed switch type, optical type, semiconductor magnetic transistor and so on. The measurement range is from 0 to 360 degrees, the precision is better than 0.5 degrees, and the bending angle is up to 0.1 degrees. There are many kinds of speed sensors, such as sensitive wheel rotation, sensitive power transmission shaft and sensitive differential driven shaft. When the speed of the vehicle is higher than 100km/h, the general measurement error is larger. The non contact photoelectric speed sensor should be used, the speed range is 0.5km/h to 250km/h, the repetition precision is 0.1%, and the distance measurement error is better than 0.3%. 4.6 Gas Concentration Sensor-oxygen Sensor A gas concentration sensor is mainly used to detect gas and exhaust emissions in vehicle bodies. The most important thing is the oxygen sensor. It detects the oxygen content in the exhaust gas of the car. According to the oxygen concentration in the exhaust, the air-fuel ratio is measured, and the feedback signal is sent to the microcomputer control device to control the air-fuel ratio to converge to the theoretical value. The commonly used germanium oxide sensors (using the temperature of -40 to 900, 1%), chromium oxide concentration cell type gas sensor (using temperature 300 to 800 C), solid electrolyte chromium oxide gas sensor (using temperature 0~400, precision 0.5%), and two oxide oxygen sensor and two oxidation oxygen sensor. The Oxygen sensor measures the amount of unburdening oxygen that is present in the exhaust pipe and will indicate if the fuel is burning rich or lean. A faulty oxygen sensor will cause the car to idle poorly and jerk as well as cause high fuel consumption. Gas concentration sensor Compared with the germanium oxide sensor, the titanium dioxide oxygen sensor has characteristics like basic structure, lightness, cheapness, and strong resistance to lead pollution. The two zirconia micro ion sensor consists of calcium oxide stable oxidation plasma, porous platinum thick film working electrode, palladium/oxidation, and thick film parameter electrode, water layer, electrode contact, and guard layer. titanium dioxide oxygen sensor Among them, the stable oxidation of calcium oxide is deposited by reactive sputtering. Working electrodes and reference electrodes are made by thick film technology. The output voltage of the ideal A/F point is abrupt, the ratio of air to air is higher, the output voltage of the oxygen sensor decreases when the oxygen concentration is added in the exhaust gas; when the air-fuel ratio becomes lower and the oxygen concentration in the exhaust gas decreases, the output voltage of the oxygen sensor is increased. The electronic control unit recognizes the mutation signal and corrections the injection volume, so as to adjust the air-fuel ratio accordingly and make it change near the ideal air-fuel ratio. At present, the NOx sensor is more and more strict for the diesel exhaust emission of NOx and PM. To cope with this limitation, it is not enough to improve the combustion mode of diesel engines. Therefore, post-processing technology is more and more valued. The selective reduction catalyst (SCR) method is one of the NOx purification techniques. The NOx in the tail gas can be selectively adsorbed to the catalyst. By spraying urea to the catalyst, the NOx can be decomposed into nitrogen, water, and discharge by reduction reaction. The sensor in urea SCR can detect whether the dosage of urea water needed for SCR is suitable. This sensor is essential for reducing agents using nitrogen oxides (NOx) as urea water purifiers. Knock sensor detonation sensor is used to detect engine vibration, by adjusting ignition advance angle and avoiding detonation. Detonation can be detected in three ways, namely cylinder pressure detection, engine block vibration, and combustion noise. The detonation sensors have magnetostrictive and piezoelectricity. The use temperature of the magnetostrictive detonation sensor is -40 C ~125 C and the frequency range is 5~10kHz; the piezoelectric detonation sensor has a sensitivity of 200mV/g at the center frequency 5.417kHz and has good linearity in the range of 0.1g~10g. titanium dioxide oxygen sensor has characteristics like basic structure, lightness, cheapness, and strong resistance to lead pollution. The two zirconia micro ion sensor consists of calcium oxide stable oxidation plasma, porous platinum thick film working electrode, palladium/oxidation, and thick film parameter electrode, water layer, electrode contact, and guard layer. V. Application of Vehicle Sensor in Vehicle Chassis Electronic Control System Chassis sensors are sensors distributed in the transmission control system, the suspension control system, the power steering system, and the braking system. They are different in different systems, but the working principle is the same as the sensor in the engine, which is mainly used in the following. Suspension sensors are used to control and control vehicle dynamics by interfering and adjusting the characteristics of vehicle suspension components. The continuous damping control system (ADC) consists of 4 control units, CAN, 4 wheel vertical acceleration sensors, 4 body vertical acceleration sensors, and 4 damper proportional valves. According to the vehicle movement and the information detected by these sensors, the optimal damping coefficient of each wheel suspension damper is calculated, the height of the car is adjusted automatically, the change of the vehicle posture is suppressed, and the control of vehicle comfort, handling stability and driving stability is realized. The system is realized by the electronic control of the steering angle of the wheel. The common system has the active front-wheel power steering system ESP, the active front-wheel superposition steering system AFS, and the active rear-wheel steering system RWS. The sensors used mainly include the speed sensor, engine speed sensor, torque sensor, and so on, which make use of these sensors to make the power steering control system realize steering control light, improve response characteristic, reduce engine loss, increase output power, save fuel and so on. Whether it is ESP, AFS, or RWS, the principle of it is the driver's manipulation instruction, which senses the condition of the road surface by the sensor, and passes the network to the electronic controller and the actuator in the form of the electrical signal. (1)The anti-lock braking sensor of the ABS system mainly uses the wheel angular velocity sensor to detect wheel speed. When the slip rate of each wheel is 20%, the brake oil pressure is controlled, the braking performance is improved, and the vehicle handling and stability are ensured. In this system, the wheel speed sensor is a very important part of ABS. It needs to provide reliable and precise wheel speed to ECU in time. The sensors have electromagnetic, Holzer, and magnetoresistance. (2)TCS system, when the driving torque of the vehicle driving wheel is too large, the driving wheel will move relative to the ground. It is generally hoped that the slip rate of the driving wheel should not exceed 20%. This system of control for driving wheel skating is called the TCS system. It is developed on the basis of ABS. In most cars, TCS and ABS share an ECU. They identify and judge the driving condition of a vehicle based on the signal input by sensors. (3)ESP electronic stabilization system ESP is an active safety system with good maneuverability and direction stability by adjusting the size and matching of the longitudinal force of the wheel to control the yaw motion of the car. The basic principle of ESP is to identify the expected motion state of a driver by means of sensors and operational logic. In order to identify the driver's expectation of the car and know the actual motion state of the car, the ESP system needs more sensors than ABS and TCS. They are hydraulic sensors of steering wheel sensor, vehicle yaw rate sensor, lateral acceleration sensor, and brake master cylinder. VI. Sensor Application in Automobile Safety System Safety is the primary factor for automobile consideration, and there are many sensors for safety, such as micro accelerometers for automobile airbags, surface micromachined gyroscopes of angle measurement rate, etc. Microaccelerometer micro accelerometer is usually composed of a parallel cantilever beam, one end of the beam is fixed on the frame and a small mass block (about 10mg) is suspended at the other end. When there is no acceleration, the mass block is not moving. When there is a vertical acceleration, the mass block is moving, the acceleration is sensitive to the acceleration, and the signal is converted to the output by C/V transformation and phase-sensitive demodulation. According to the detection mode, the micro accelerometer has several kinds of piezoresistive, capacitive, tunnel, resonant, and thermal forms. The capacitance micro accelerometer has high sensitivity, low noise, small drift and a simple structure. It is widely used in automobile airbag systems and anti-skid systems. The mass of capacitance micro accelerometer mass block moves downward when it has acceleration and changes the distance from another electrode on the frame. The displacement of mass movement can be obtained by measuring the change of capacitance. The main structure is divided into suspension. The arm swing type and comb-like folded beam type are changed into other types. The structure of the former is relatively simple, and the bulk silicon processing method is mostly used. The simple pendulum type structure consists of the upper and lower fixed electrodes and the movable sensitive silicon cantilever beam electrode, the anisotropic corrosion of the semiconductor plane process, and the encapsulation of the electrostatic sealing technology. The latter can be regarded as the combination of the cantilever beam and the combination. The design is much more complicated. The micromachining method is mainly based on surface sacrificial layer technology. The isotropic properties of the polysilicon material can guarantee the symmetry of the micromechanical properties, the precision of the batch processing is high, and the sensitive parts of this structure are small in size, and the monolithic integration of the peripheral circuits is realized. Micromachined gyroscope (MEMS) micromachined gyroscope (MEMS) is a vibrational angular rate sensor, which has attracted much attention in the application and development of automobiles. It is mainly used in GPS signal compensation and chassis control system for automobile navigation. There are two vibration modes in the micromechanical gyroscope, one is the transverse vibration mode, that is, the mode of driving vibration, which is usually called the reference vibration, which will produce additional motion under the action of the Coriolis force; the other is the normal vibration mode, the sensitive vibration mode, the detection of the additional movement of the Coriolis force, and the angular rate information contained in the Coriolis force. According to the material used, the micromachined gyroscope is divided into two kinds of quartz and silicon vibrating beams. The quality factor of quartz material has the highest Q value, the top characteristic of the gyroscope is the best, but the quartz processing is difficult and the cost is very high. Silicon material has complete structure, good elasticity, and easy to get high Q value micromechanical structure, which has become the mainstream of low-cost research and development at present. The structure of the silicon micromachined gyroscope, the vibration beam structure, the double frame structure, the plane-symmetric structure, the transverse fork structure, the comb tuning fork structure, the beam island structure are used. The driving modes for the reference vibration are electrostatic, piezoelectric, and electromagnetic driving. The detection methods of additional vibration caused by the Coriolis force are capacitive detection, piezo detection, and piezoresistive. Testing. The gyroscope design with electrostatic drive and capacitance detection are the most common. Some of the products have been developed successfully. Vehicle monitoring and self-diagnosis sensor in-vehicle monitoring and self-diagnosis, the main application of vehicle sensors will be tire pressure monitoring, followed by sensors applied to cooling, braking, and other systems. In addition, such as the use of light sensors in the luminance control system, the use of magnetic sensors and airflow velocity sensors in the driving system, the use of indoor temperature sensors, suction temperature sensors, air volume sensors, sunshine sensors, and humidity sensors in the automatic air conditioning system, and the use of azimuth sensors and speed sensors in the steering system. The collision sensor is the main control signal input device in the airbag system. The effect is when the vehicle collides on the road, the collision sensor is used to detect the intensity signal of the car collision, and the signal is entered into the airbag computer. The airbag computer determines whether the inflatable element is detonated to inflate the airbag according to the signal of the collision sensor. After the transformation of many countries, many cars are also equipped with side airbags. When the car has a lateral collision, the airbag will also be inflated, so a system equipped with a lateral airbag is equipped with a collision sensor on the left and right sides of the car. This is more humane in ensuring the safety of vehicle users. The lateral tilt angle sensor is an effective method to prevent the car from turning over the car during driving. It is an important measure to improve the safety of the car, especially the high gravity cars, such as the off-road vehicle and the double-deck passenger car, which is more necessary. Take an example, an angle sensor made with the principle of gravity. The mass of the swing part is m, and the distance between the center of gravity and the shaft is L. When the car body tilts or curves, it can make the swing part deflect. The force analysis in Figure 1 is an ideal state without any friction. The force F is the result of the joint action of the sliding force F1 and the centripetal force F2. The force F is proportional to the tilting force, and the beta-generated deflection angle is proportional to the tilting force. The resultant force T of the gravitational G and F in the oscillating part is the tension of the pendulum, and the swing angle of beta =tg-1 (F/G) is independent of L. When the mass m is fixed, the beta is only related to F and is proportional. In fact, due to the existence of friction on the shaft, the longer the L is, the larger the swing torque is, the higher the accuracy. Angle sensor is usually used as a sampling element in the control system, and its performance plays an important role in the whole system. The potentiometer angle sensor has been widely used in all kinds of control systems, but its disadvantage is the existence of sliding wear and electrical noise of the contact. The magnetic sensitive resistance angle sensor is a new pure resistive element made of semiconductor technology. It is characterized by no contact. When the swing partial deflection, the flux of the magnetic resistor is changed to make the resistance of the magnetic sensitive resistance several times. The above changes fundamentally eliminate the electrical noise and improve the accuracy. All kinds of angle sensors have a damping function so that there is a short delay in response to the measured angle, which is beneficial for the control system. VII. Other Major Automotive Sensors Alcohol detection MEMS system is a new type of integrated alcohol sensor, which can adsorb oxygen according to the oxygen concentration in the environment and change the resistance value. In normal conditions, the element can keep a certain resistance value after the oxygen is adsorbed in the air, and once the air contains alcohol, the oxygen element on the surface of the element will react with the alcohol to reduce the resistance value. By measuring the resistance value, we can detect the alcohol concentration in the breath. The alcohol detection MEMS sensor will be embedded in the sealed shell of the diameter 8mm, together with the signal processing circuit and so on, and will be embedded in the steering wheel together. Once the driver's exhaled gas contains alcohol, a safety alarm will be issued. When the raindrop is hit on the glass of the induction zone, the intensity of the light reflected by the raindrop will change because of the rainfall or moisture content on the glass and changes the brushing frequency of the wiper. Or through the infrared electronic rainfall sensor to induce the amount of rainfall, and automatically adjust the speed of the wiper with the change of speed to improve the driver's driving convenience to make the driving safer. The tire pressure monitoring system installs highly sensitive sensors on each tire to monitor the tire condition at any time in the driving state and transmit it wireless to the receiver through a sensor to enable the driver to grasp the condition of the tire at any time, to ensure the safety of the car, to prolong the service life of the tire and to reduce the consumption of the fuel. The most advanced direct tire pressure monitoring solutions include advanced warning systems, pressure, temperature, voltage and motion detection. When the oil viscosity sensor changes the oil, it usually depends on the time or mileage specified by the manufacturer. A few manufacturers have adopted a more advanced way to calculate the oil exchange interval by recording engine speed and temperature. VIII. Automotive Sensors Market Size--Its Market Trend Because of the important role of automotive sensors in the automotive electronic control system and the rapid growth of the market demand, all countries in the world have paid great attention to its theoretical research, new material application, and new product development. The development trend of automotive sensor technology in the future is miniaturization, multi-function, integration, and intelligence. The microsensor with low cost and high performance can be designed by means of micro electro mechanical system (MEMS) technology and computer-aided design technology. At the current level of technology, micromachining technology has been able to produce microstructures with different levels of 3D, and then produce tiny sensor sensors with very small sizes. Because the components are relatively small, the use is relatively convenient and efficient, making the economy improved. Multifunction means that a sensor can detect 2 or more two characteristic parameters or chemical parameters, thus reducing the number of sensors and improving the reliability of the system. Integration refers to the use of IC manufacturing technology and fine processing technology to make IC sensors. Intelligentization refers to the combination of sensors and large-scale integrated circuits with CPU, which is intelligent, to reduce the complexity of ECU, to reduce its volume, and to reduce the cost. In addition, the development of new materials is an important basis for sensor technology. Now new materials, such as optical fiber, nanomaterials, superconducting materials, have opened a new world for the development of sensors. With the development of research, more and more new sensor materials will be developed. The function of the sensor is not only related to its material, but also to its processing technology. Micromachining technology has been increasingly used in the sensor manufacturing process. With the development of modern manufacturing technology, more advanced manufacturing technologies will be applied to the manufacture of automotive sensors. The principle of the sensor is based on various physical, chemical, biological effects, and laws, which enlightens people to further explore sensitive functional materials with new effects and to develop new sensors with new principles. This is an important way to develop low-cost, high-performance, multi-functional, and miniaturized sensors. FAQ 1. What is a sensor in automobile? Automobile sensors are intelligent sensors which can be used to control and process the pressure of oil, temperature, level of emission, coolant levels, etc. There are different types of sensors used in automobiles, but knowing the working of these sensors is essential. 2. How many sensors does a car have? Currently, each vehicle has from 60 to 100 sensors on board and we can expect that number to rise as cars get 'smarter'.” In fact, recent industry figures suggest the number of sensors is projected to reach as many as 200 per car based on current trends. 3. What is the importance of sensors in the automobile? Sensors monitor vehicle engines, fuel consumption and emissions, along with aiding and protecting drivers and passengers. These allow car manufacturers to launch cars that are safer, more fuel efficient and comfortable to drive. 4. How do vehicle sensors work? Using echo-times from sound waves that bounce off nearby objects, the sensors can identify how far away the vehicle is from said object, and alert the driver the closer the vehicle gets. Electromagnetic sensors create an electromagnetic field around the bumper, and offer an alert whenever objects enter it. 5. How many sensors does a F1 car have? 300 sensors. With help from over 300 sensors on each car, McLaren's F1 ECU deals with over 1000 input parameters and transmits more than 1.5GB of live data back to the garage during an average 300km grand prix. 6. Where are sensors located on cars? Depending on the vehicle engine model, you often have 1 to 4 exhaust gas temperature sensors. The sensors are installed on the exhaust pipe and the exhaust manifold, and sometimes also on the turbocharger. The sensors are often quite expensive and can be difficult to reach and replace; they often rust and get stuck. 7. How long do car sensors last? Newer oxygen sensors are supposed to work efficiently for 60,000 to 90,000 miles, depending on the model of your car. If your mechanic determines that your car's problem is due to a bad or failing oxygen sensor, the replacement shouldn't take long and you'll be ready to tackle many more miles on the road. 8. Do all cars have sensors? Modern cars have an increasing amount of sensors. Most cars have an oxygen sensor and a throttle position sensor, but parking sensors are optional. Professional mechanics agree that one of the most important evolutions to come about in recent years is the expansion of sensors to monitor mechanical systems. 9. How do I know if my upstream or downstream oxygen sensor is bad? A decrease in fuel efficiency can be a telltale sign that an O2 sensor is not performing as it should. This can happen because of a fuel mixture that is either too lean or too rich. Such a swing in A/F ratio is a sign that an upstream or control sensor is faulty. 10. What does a car do when the oxygen sensor is bad? If your oxygen sensor is failing, then its readings will be inaccurate, again, resulting in a sub-optimal fuel-to-air composition. Your car's performance isn't the only thing that is harmed by a malfunctioning oxygen sensor - it can do damage to the environment as your car's emissions will increase drastically.
kynix On 2018-04-02
Ⅰ IntroductionAn operational amplifier, or op-amp for short, is fundamentally a voltage amplifying device designed to be used with external feedback components such as resistors and capacitors between its output and input terminals. Learn more about the most common opamp basics, essential knowledge when selecting and using an op amp in electronics. We can conclude our section and look at Op Amp basics with the following properties and questions. Opamp Basics: Op-Amp CircuitsCatalogⅠ IntroductionⅡ Amplifier Figures of MeritⅢ Q & AⅣ Application: LM358 Classic CircuitsⅡ Amplifier Figures of MeritNegative FeedbackIt is a important technique to improve bandwidth and distortion and control gain.Open-loop GainIt refers to the ratio of the voltage change at the output of the amplifier to the voltage change at the input when the amplifier input and output are open. Common-mode Rejection Ratio (dB)It is the ratio of the amplifier's amplification factor of the differential voltage signal to the amplification factor of the common mode voltage signal.Input Current NoiseIt is the equivalent current noise applied in parallel with the input of the noiseless amplifier.Output CurrentIt refers to the current driven by the load at the output of the op amp. It is usually a function: input overdrive, correlation between output voltage and power supply, temperature, source, and drain characteristics will differ.Phase MarginIt is the phase shift between an output of the same frequency and an inverting input in an open-loop circuit.Voltage GainIt is the ratio of the change in output voltage to the change in input voltage.Programmable Gain BufferIt can set the gain resistance of the op amp (integrated on the template), and the gain can be set to +1, +2, or -1 through simple external connections.Saturation VoltageIt is the voltage between the collector and emitter of the transistor under saturation conditions. In the saturated state, the emitter-base and collector-base are forward biased, so that the voltage between the collector-emitter is very low.Rise TimeThis refers to the time required for the output voltage to change from 10% of its final value to 90% of its final value.Unity-gain BandwidthIt refers to the frequency at which the amplifier's open-loop gain is equal to one. If the op amp frequency response has a single-pole roll-off, the unity-gain bandwidth is equal to 1UGBW.Strobe “OFF” VoltageThe strobe “OFF” voltage is the minimum voltage at the strobe pulse and is guaranteed not to interfere with the comparator operation.Input Current IndexIt refers to the average of the current drawn from the two input pins. In addition, the input current is also commonly called bias current.Gain Bandwidth ProductIt refers to the product of the amplifier's bandwidth and the gain at which the bandwidth is measured.Large Signal Voltage GainIt refers to the ratio of the change in output voltage to the change in input voltage. This parameter is usually specified at a large output voltage, smaller than the maximum output voltage, which is the typical value under direct current conditions.Offset Voltage Temperature CoefficientIt refers to the average rate of change in offset voltage due to changes in junction temperature within a specified temperature range.Output High VoltageIt refers to the high DC output voltage of the comparator, which produces the high output current. And it is usually related to the totem pole or push-pull output of the comparator.Input Source CurrentIt refers to the maximum output positive current produced under the comparator's push-pull output state.Total Harmonic Distortion (THD)When a pure sinusoidal signal is input to the op amp as Vin (w) = Vpsin (wt):Input harmonic distortion: Vout(w)a1Vpsin(wt)+a2Vpsin(wt)+...+anVpsin(nwt)The expression of THD is: THD(%)=[sqrt(a2xa2+a3xa3+...+anxan)/a1]x100Common-Mode Input Impedance (RINCM)It refers to the ratio of the change in the common-mode input voltage to the change in the input current at the inverting or non-inverting terminal.Output Low VoltageIt refers to a low DC output voltage. The output drive is a low voltage sink current. This specification is usually related to the totem pole or push-pull output of the comparator.Using a CMOS op amp as the output driver, although the circuit works well, but requiring a 1m shielded cable, and the oscillation of the operational amplifier is about 1MHz when there is no input signal. If shorten the cable to 10cm, the oscillation is stable.Some op amps are not suitable for driving capacitive loads directly, such as long shielded cables, which is a capacitive load. In addition, coaxial cables have about 60-100pF capacitance per meter.Harmonic DistortionIt refers to the unwanted spurious signals generated at the amplifier output due to the non-linearity of the signal line. When the input is a sinusoidal signal, these spurious signals will appear as integer times of the input frequency (for example, second harmonic, third harmonic).Output Leakage Current (ILEAKAGE)It means that the current enters the comparator output (the output is driven high). It often appears at the output of open collector and open drain.Power Supply Rejection Ratio (PSRR)It refers to the ratio of the change in the input offset voltage to the change in the power supply voltage, PSRR (dB) = 20log10 (DVOS / DVS)Linear Phase DeviationIt refers to how a closed-loop phase response of an operational amplifier approaches and follows the linear relationship between phase change and frequency in a specific frequency band.-3dbIt refers to the frequency when the value of the small signal output amplitude of the closed-loop amplifier decreases to 3dB.Common-mode Voltage RangeIt refers to the typical value of the voltage range at the input, which determines the performance of the amplifier.Specified Power Supply RangeIt describes the power supply voltage required for the operational amplifier to operate.Output Absorption CurrentIt refers to the highest output negative current of the comparator.Output Voltage SwingIt refers to the maximum peak-to-peak swing of the output voltage under a specific load and power supply voltage.Current FeedbackIt refers to a technology used in current feedback amplifiers whose output signal reflects the value of the current input to the inverting input (transimpedance gain function). In some aspects, this topology has operational advantages over traditional voltage feedback.Closed Loop BufferIt refers to an amplifier with high input impedance and low output impedance and a fixed gain of +1. Its typical applications are used for isolation, increased output drive, capacitive load, etc., in addition, there is no need to set the gain resistance.Closed-loop Gain It is the ratio of the change in the output voltage to the change in the input voltage after the feedback and input network added. Generally, this value is set using an external resistance.Common-mode RangeThe common-mode range, also known as the input voltage range, is a measure of the range of input voltages that the input pins of an op amp can accept. This specification is usually relative to the power supply amplitude.Output ImpedanceIt refers to the ideal series output impedance of the ideal operational amplifier when there is no impedance, which is the approximate output impedance of the op amp measured under AC conditions.Transient ResponseIt refers to the step function response of the closed-loop system of the amplifier under the condition of small signal (usually less than 100mV).Slew RateWhen given a transition or square wave input, the amount of change in the amplifier's output from one level to another. Typical values are averages of values measured based on a change in total output voltage from 10% to 90%.Response TimeIt is the time interval when the input step function makes the output from the initial value to the logic threshold voltage.Unity Gain FrequencyIt refers to the frequency at which the gain of the voltage feedback op amp is 1 (0 dB). For an ideal operational amplifier, its gain-bandwidth product is equal.Intercept PointIt refers to the output power of the fundamental frequency, which is equal to the power value of the fundamental frequency in the specified distortion term (2nd, 3rd, or 3rd intermodulation).Input Offset CurrentIt refers to the current difference between the two inputs.Voltage OverdriveIt means that a certain amount of input step voltage exceeds the minimum drive input voltage required by the comparator to change from one logic level to the opposite logic level.Differential Gain & Differential PhaseDifferential gain refers to the change in the input and output of the gain, and differential phase refers to the phase change in the input stage. They are video measurements, and are a standard measurement in the broadcasting field to measure relative changes in the interpretation of video signal consistency.Voltage FeedbackA technique used in traditional operational amplifiers, where part of the output voltage is fed back to the input, and the voltage difference between the two inputs is amplified by the operational amplifier. Avol Open-loop Voltage Gain“A” is a sign of gain. The letter “V” written below indicates the gain of voltage, and the letter “ol” also written below is an abbreviation for open loop. Open-loop voltage gain refers to the gain (Vout / Vin) of the amplifier without feedback. Due to the existence of the bias voltage, these errors must be compensated.Logic Threshold VoltageIt refers to the voltage that causes the comparator output state to change when the input offset voltage is exceeded.Output ResistanceIt refers to the value of the series resistance at the output of an ideal op amp with zero output resistance, which measured under DC conditions.Gain FlatnessIt refers to the volume of gains “violently increasing” and “rapidly decreasing” in a given bandwidth range measured in decibels (dB), which affects the most important parameter specifications such as phase margin, gain margin, and closed-loop gain.Offset Current Temperature CoefficientIt refers to the average rate of change in deviation current due to changes in junction temperature within a specified temperature range.Input ImpedanceIt is the ratio of input AC voltage to input AC current.Input Voltage NoiseIt refers to the equivalent voltage noise in series with a noiseless amplifier.Input Offset VoltageIt is the product of the DC error voltage between the inputs and the closed-loop gain, because of the non-ideal balance between the input stage and the output is caused by the DC error voltage of the input terminals.Gain MarginOpen loop gain when the phase between the inverting input and output crosses zero at a certain frequency.Supply CurrentIt refers to the current required from the power supply to the unloaded amplifier and to the power supply at the output midpoint.Settling TimeIt refers to the time between the input step function initial value and the output voltage reaching the specified error band. The error band refers to the percentage of the total voltage change.Differential Input ResistanceIt is the ratio of the change in the input voltage to the change in the input current.Ⅲ Q & AQ1: What is the difference between a voltage feedback amplifier and a current feedback amplifier?A: The internal circuits of these two op amps are different. The voltage feedback op amp is restricted by the internal design, and it only has a very low input bias current, but there is no internal limit on the differential input voltage, because it is limited only when external feedback is required. In contrast, for a current feedback amplifier, its differential input voltage is subject to internal design, but it does not limit its input bias current, so it is limited only when external feedback is required.Q2: What is the difference between open and closed loops?A: The open loop gain is actually the internal gain of the op amp without feedback, and usually takes any value between 1,000 and 10,000. Closed loop gain is the gain of the entire circuit, which is equal to the open loop gain divided by 1 plus the loop gain (the improvement coefficient). In fact, the gain of the op amp when there is no feedback is the open loop gain, and the gain when feedback is considered is closed-loop gain.Q3: If the op amp has ideal AC characteristics, the Bode plot (gain-frequency response) is a unipolar system. What is the gain slip rate in dB / decade?A: In a unipolar system, the gain drops (or decreases) at 20dB / decade, which is 6dB / octave. This is responsive to any single pole, and it is also suitable for a simple RC filter or an ideal operational amplifier. However, because op amps have more high-frequency poles, the phase shift will begin to increase as the frequency approaches the unity gain frequency of the op amp.Q4: What is the difference between unity gain bandwidth, gain bandwidth product (GBP), and -3dB frequency?A: Many op amps have an open-loop gain reduction rate of -20db / decade when the frequency is stable. At any point during this descent phase, the GBW is a constant. If the unity-gain operation of the op amp is stable, then the unity-gain bandwidth, or the frequency at which the open-loop gain is 1, is usually equal to GBP. In addition, GBP is not equal to (usually higher than) the unity gain bandwidth. The -3dB frequency is a measure of the bandwidth of an operational amplifier when it is operating in a closed loop. The -3dB point is the frequency at which the gain of the overall closed-loop system drops by 3dB. The unity gain frequency for closed loop applications can be calculated using BW=GBP/Av. The -3dB frequency and unity-gain bandwidth applied depend on the feedback gain setting, output swing, load, and circuit layout.Q5: Why do some amplifiers oscillate with a capacitive load?A: The output impedance of the op amp and the capacitance of the capacitive load may form a resistance-capacitance oscillation. Also they form an R-C oscillation at the output stage, which causes additional phase lag in the feedback signal. CMOS amplifiers have a high output impedance which will cause the electrodes to be approached or lower the unity gain frequency of the op amp. The additional phase lag of the electrodes will weaken the phase margin of the op amp The total phase lag of the amplifier causes the phase angle of the unity gain frequency to increase by more than 180 degrees to cause the total feedback phase shift in unity gain to exceed 180. degree. In addition, the output impedance of a CMOS amplifier is between 100 and 500, causing a relatively low pole frequency. And meanwhile, the output impedance of the high-speed bipolar operational amplifier is in the range of 1 to 100, which causes the pole frequency to be much higher than that of the CMOS operational amplifier, so that the pole is far from the unity gain frequency of the device. The drive of a CMOS amplifier to a capacitive load can be improved by placing an output resistor at the output and an external positive feedback capacitor.Q6: If the output of the op amp stays close to the voltage rail, that is, the output rail, what is the reason?A: There are many ways for operational amplifiers to “rail”. The difficulty is keeping it away from the "rail". If the input exceeds the input voltage range, the output is usually near to a supply voltage rail. In theory, if the output exceeds the actual supply voltage, and a higher supply voltage is given, the op amp will go to rail output again. If there is no feedback or the polarity of the feedback is wrong, the op amp goes to rail output again. At the same time, if the non-inverting input is higher than the negative inverting input, the op amp also goes to rail output. The application of the operational amplifier should be analyzed to ensure that the power supply voltage used has a proper input and gain, so that in normal operation, its input voltage is within the rated value and the output voltage is within the normal range.Q7: What is the difference between the common-mode voltage and input voltage range of an op amp?A: Common mode voltage means that one voltage is applied to both inputs at the same time. Input voltage range is the range of voltages that can be accepted by the input pins. It is necessary to remember that the op amp should suppress the common-mode voltage, and amplify the difference between the two input pins only.Q8: The SPICE model of the bipolar operational amplifier works well, but the SPICE model of the CMOS operational amplifier does not work. Is there a need to set SPICE?A: To input the appropriate bias current to the model, the SPICE model applied on CMOS operational amplifier needs to set the default GMIN option to the largest SPICE package value.Q9: What is the difference between the amplifier's output current and short-circuit current?A: Short circuit current refers to the current generated by the device if the output is connected directly to the power line. This indicates that the output current is limited depending on the design of the device. However, the short-circuit current does not represent the true output of the drive capability of the output. Due to the impedance characteristics of the output stage, the maximum output current is determined by the swing of the output voltage under load. In facet, the smaller the load, the larger the output swing; the larger the load, the smaller the output swing.Q10: How to check the stability of an op amp circuit?A: Check the stability of the control loop, such as the pulse load and related changes in output voltage. The pulse load may be a load current with a pulse or step change, so that the output of the op amp circuit should be connected to a series R-C circuit. The greater the circuit swing or vibration, the worse the stability of the circuit.Q11: Are there any good ways to minimize noise when amplifying a low-level DC signal?A: To obtain a high signal-to-noise ratio, the circuit must be well designed. This includes choosing the best amplifier bandwidth and knowing the impedance of the input signal. If the input signal source has a fairly high impedance, it makes no sense to choose a low voltage noise amplifier, which has high current noise.Q12: How should design a low frequency (<1Hz) differentiator to minimize the output noise?A: The only reason that the output of the differentiator contains noise is because there is a lot of gain and the input is noisy. The traditional differentiator uses Rs-Cs in series at the input and the Rf-Cf in parallel near the operational amplifier. It is not necessary to try more Rs or Cf to minimize noise. The noise of the output come from the differentiator does not mean that it is harmful, because it also amplifies useful signals. In addition, if disconnect a loop, the differential output noise may be beneficial and will stabilize the loop. If the output of the differentiator is quite noisy or has too much input noise, analyze which are the real sources of them.Q13: How to protect the amplifier input from being higher or lower than the supply voltage?A: What must be done is either to clamp the input of the device, or to limit the input current of the device, or ideally, do both. The easiest way is to choose a current limiting resistor to limit this current. The selection is based on the fact that the current generated by the circuit input at the maximum input voltage is less than the maximum current rating of the input pin. Usually, a 1K to 100K resistor in series with this input pin is effective. However, since the signal is usually connected directly to a non-inverting input pin, a non-inverting amplifier may need a protective resistor connected to this pin. For high impedance circuits, a large resistor and or low leakage current diode can be used.Q14: What is the difference between a single-supply amplifier and a dual-supply amplifier?A: There is no difference in the actual circuit, layout, and characteristics of the amplifier. When an operational amplifier is designated as dual power supply, the output load is usually referenced to ground (GND), while a single power supply operational amplifier is usually referenced to the midpoint voltage of a single supply, and it is usually specified to operate on lower voltages, but this is not a necessary requirement. Therefore, whether the op amp is powered by a single 5V power supply and ground (GND), or powered by +2.5 and -2.5V, these is no different. Ⅳ Application: LM358 Classic CircuitsThis Video is Going to Show Top 5 Electronics Project Using OP-AMP LM358The LM358 includes two independent, high-gain, internal frequency-compensated dual operational amplifiers. It is suitable for single-supply operation with a wide range of power supply voltages. It is also suitable for dual-supply operation. LM358 applications include sensor amplifiers, DC gain modules and all other operational amplifiers that can be powered by a single power supply. The classic circuits of LM358 are as shown as following:Figure 1. Active DC-coupled Low Pass RC Filter Figure 2. LED Driver Figure 3. Transistor-Transistor-Logic (TTL) Drive Circuit Figure 4. Active RC Band Pass Filter Figure 5. Squareware Oscillator Figure 6. Hysteresis ComparatorFigure 7. Active Band Pass filter Figure 8. Lamp Driver Figure 9. Current Monitor Figure 10. Low Drift Peak Detector Figure 11. Voltage Follower Figure 12. Power Amplifier Peripheral CircuitFigure 13. Voltage Controlled Oscillator VCOFigure 14. Fixed Current Source Figure 15. Pulse Generator Figure 16. AC Coupled Non-inverting Amplifier Figure 17. AC Coupled Inverting Amplifier Figure 18. Adjustable Gain Instrumentation Amplifier Figure 19. DC Amplifier Figure 20. Pulse Generator Figure 21. Bridge Current Amplifier Figure 22. Introducing Differential Input Signal Figure 23. DC Differential Amplifier Frequently Asked Questions about Op Amps Basics1. What is an op amp basics for dummies?An op amp is a super-sensitive electronic amplifier circuit that's designed to amplify the difference of two input voltages. Thus, an op amp has two inputs and one output. ... Most op amps require both a positive and a negative voltage power supply, with voltages usually ranging from 6 V to 18 V. 2. What is the basic use of op amp?An operational amplifier is an integrated circuit that can amplify weak electric signals. An operational amplifier has two input pins and one output pin. Its basic role is to amplify and output the voltage difference between the two input pins. 3. What is operational amplifier and its types?An operational amplifier (op amp) is an analog circuit block that takes a differential voltage input and produces a single-ended voltage output. Op amps usually have three terminals: two high-impedance inputs and a low-impedance output port. 4. Which purpose the op amp is used?As the name suggests, the purpose of an amplifier or an op amp is to amplify or increase the input signal to produce an output signal which is much larger than that of the input, with a similar waveform as that of the input. The main change in the output signal will be the increase in the power level. 5. What does it mean when an op amp saturates?Originally Answered: What happens when an op-amp is saturated? that means the amplification or gain is so high as to make the output signal with a given input signal, so large as to exceed the compliance range of the power supply of the ope amp. More simply put, if you have an op amp supplied with +/-15V supply rails.
kynix On 2019-12-28
Ⅰ IntroductionAs we all know, capacitors have always played a very important role in electronic circuits. They are responsible for the coupling of signals in electronic circuits, the differentiation of volt-ampere characteristics in RC circuits, such as integration, the "channel" in oscillating circuits, bypass and power filter, etc. Aluminum electrolytic capacitor is made of anodized aluminum foil, corroded cathode aluminum foil and electrolytic paper in the middle, then impregnated with working electrolyte and sealed in aluminum shell. CatalogⅠ IntroductionⅡ Common problems of electrolytic capacitor 2.1 Why can't an aluminum electrolyte capacitor withstand reverse voltage? 2.2 What are the similarities and differences between nonpolar capacitance and polar capacitance? 2.3 What will happen when a polar capacitor is reversed? 2.4 The reverse connection of the polar capacitor will explode. Does it mean that it can't be directly connected to the AC power supply? 2.5 If the polarity capacitor is reversed, why is it short-circuited? 2.6 Why does the resistivity of electrolytic capacitor become smaller when the positive and negative poles are reversed? 2.7 Why can we only use a nonpolar capacitor in a pure AC circuit? 2.8 What is electrolytic capacitance? 2.9 The characteristics of electrolytic capacitors are as follows 2.10 What are the similarities and differences that cannot be ignored between polar and nonpolar capacitors in performance, principle and structure?Ⅲ SummaryⅣ FAQ Ⅱ Common problems of electrolytic capacitor2.1 Why can't an aluminum electrolyte capacitor withstand reverse voltage?Due to the polarity of electrolytic capacitors, it is necessary to pay attention to the correct connection of positive and negative electrodes in use, otherwise, not only the capacitors can not play a role, but also the leakage current is very large. In a short time, the inside of the capacitors will heat up, damage the oxide film, and then damage. As shown in the figure, the basic structure of the aluminum electrolytic capacitor is composed of an anode, aluminum layer attached to the insulating medium, cathode aluminum layer of the receiving electrode and the real cathode composed of electrolyte. The electrolyte is soaked in the paper between the two aluminum layers. Aluminum oxide layer is plated on the aluminum layer, which is very thin compared with the voltage applied on it, and it is easy to be broken down, leading to capacitor failure. The alumina layer can withstand the forward DC voltage. If it bears the reverse DC voltage, it is easy to fail in a few seconds. This phenomenon is called the "valve effect", which is why the aluminum electrolytic capacitor has polarity. If both electrodes of the electrolytic capacitor have an oxide layer, the non-polar capacitor will be formed.Many articles report the mechanism of the threshold phenomenon of the reverse voltage of the aluminum electrolytic capacitor, which is called the hydrogen ion theory. When the electrolytic capacitor bears the reverse DC voltage, that is, the cathode of the electrolyte bears the positive voltage while the oxide bears the negative voltage, The hydrogen ions gathered in the oxide layer will pass through the medium and reach the boundary between the medium and the metal layer, and then they will be converted into hydrogen. And the expansion force of the gas causes the oxide layer to fall off. Therefore, the current flows directly through the capacitor after breaking through the electrolyte, and the capacitor fails. This DC voltage is very small. Under the reverse DC voltage of 1 ~ 2V, the aluminum electrolytic capacitor will immediately fail due to the hydrogen ion effect in a few seconds. On the contrary, when the positive voltage is applied to the electrolytic capacitor, the negative ions are concentrated between the oxide layers. Because the diameter of the negative ions is very large, they can not break through the oxide layer, so they can withstand higher voltage.2.2 What are the similarities and differences between nonpolar capacitance and polar capacitance?Are nonpolar capacitors the same as nonpolar electrolytic capacitors? Most kinds of capacitors are nonpolar, only the electrolytic capacitors have polarity. Among them, there are very special nonpolar electrolytic capacitors. Compared with ordinary capacitors, electrolytic capacitors have a larger capacity, lower price and smaller volume than other capacitors, but electrolytic capacitors generally have polarity, and their working reliability, withstand voltage, temperature resistance, dielectric loss and other indicators are not as good as other capacitors.The so-called non-polar electrolytic capacitor is actually the back-to-back packaging of two identical electrolytic capacitors. This kind of capacitor has large loss, low reliability and low voltage withstand, which can only be used in a few occasions with low requirements.2.3 What will happen when a polar capacitor is reversed?If the capacitance capacity is very small, the withstand voltage is very high, and the working voltage is low, there will be nothing wrong with the reverse connection. If the capacity is slightly large (above 100uF) and the withstand voltage is close to the working voltage, the capacitance can just work for nearly 10 minutes, then it will bulge and burst.2.4 The reverse connection of the polar capacitor will explode. Does it mean that it can't be directly connected to the AC power supply?It can't be connected to the AC power supply, because the polar capacitor is designed to be used in the DC power supply for filtering, and there is special material inside the polar capacitor, which can not bear the backpressure. If it is connected to the AC power supply, it will breakdown reversely or explode.2.5 If the polarity capacitor is reversed, why is it short-circuited?The internal structure of the polar capacitor is divided into the positive electrode, a dielectric layer and the negative electrode. The dielectric layer has the property of unidirectional conduction. Of course, the dielectric layer of the product will not play the role of insulation after being connected reversely, and the capacitor will be short-circuited. 2.6 Why does the resistivity of electrolytic capacitor become smaller when the positive and negative poles are reversed?It involves the principle of electrolytic capacitor. When the positive electrode of the capacitor is connected positively, a very thin oxide film (alumina) will be formed as the dielectric. When the negative electrode of the capacitor is connected reversely, H2 will be produced without forming the oxide film, and the other electrode will not form the oxide film which can be used as the dielectric due to different materials. 2.7 Why can we only use a nonpolar capacitor in a pure AC circuit?In the circuit of DC voltage superposing AC signal, if we can ensure that the lowest voltage after superposing will not become negative, we can use a capacitor with polarity. In the case of the same capacity, the volume and cost of the polar capacitor are far less than that of the nonpolar capacitor, so when we need a larger capacity, the volume of the capacitor is a big contradiction. We usually replace non-polar capacitors with polar ones, which not only solves the volume problem but also reduces the cost. Large capacitance can filter the AC signal with a lower frequency and above, while small capacitance can only filter the signal with higher frequency and above. 2.8 What is electrolytic capacitance?Electrolytic capacitor is a kind of capacitor. Its medium is coated with electrolytes. It can be divided into positive and negative electrodes and cannot be connected wrongly. The capacitance is composed of two metal poles and the insulating material (medium) sandwiched between them.2.9 The characteristics of electrolytic capacitors are as follows①The capacitance per unit volume is dozens to hundreds of times larger than other kinds of capacitance.②Rated capacity can easily reach tens of thousands of μ for even several F, but it is not as good as double electric layer capacitance.③The price is much lower than other kinds because the components of electrolytic capacitors are ordinary industrial materials, such as aluminum. The equipment for manufacturing electrolytic capacitors is also common industrial equipment, which can be mass-produced at a relatively low cost. Electrolytic capacitors are usually made up of metal foil (aluminum/tantalum) as the positive electrode, and the insulating oxide layer (alumina/tantalum pentaoxide) of metal foil as the dielectric. The negative electrode of aluminum electrolytic capacitor is composed of thin paper/film or electrolyte polymer soaked in electrolyte, the negative electrode of the tantalum electrolytic capacitor is usually manganese dioxide. As both of them use electrolytes as the negative electrodes, the electrolytic capacitor gets its name. The polar electrolytic capacitor usually plays the role of power filter, decoupling, signal coupling, the time constant setting, DC isolation and so on in the power circuit or IF and LF circuits. It can't be used in an AC power circuit. When it is used as a filter capacitor in the DC power circuit, its anode (positive) should be connected with the positive end of the power voltage, and the cathode (negative) should be connected with the negative end of the power voltage. It can't be reversed, or it will be damaged. 2.10 What are the similarities and differences that cannot be ignored between polar and nonpolar capacitors in performance, principle and structure? Polar capacitance is a kind of electrolytic capacitance. It consists of two electrodes formed by the anode aluminum foil and the cathode electrolyte. A layer of aluminum oxide film produced on the anode aluminum foil is used as the dielectric of capacitance. As a result of this structure, it has polarity. When the capacitance is directly connected, the aluminum oxide film will remain stable due to the electrochemical reaction. When the reverse connection is made, the aluminum oxide layer will become thinner, which makes the capacitor easy to be broken down and damaged. Therefore, we must pay attention to the polarity of the electrolytic capacitor in the circuit. Ordinary capacitors are nonpolar. We can also connect two anodes or cathodes of electrolytic capacitors in series to form nonpolar electrolytic capacitors. ①The same principleThey both store and release charges.The voltage on the plate shall not change suddenly. (voltage here refers to the electromotive force of charge accumulation) ②Different mediaWhat's the medium? It's the material between the two plates of the capacitor. Most of the polar capacitors use electrolytes as a dielectric material, and the capacity of the polar capacitor is larger than that of the same volume. In addition, the capacity of the same volume of polar capacitance produced by different electrolyte materials and processes will be different. The withstand voltage of the capacitor is closely related to the dielectric materials used. There are also many dielectric materials for non-polar capacitance, most of which are metal oxide film, polyester and so on. The reversibility or irreversibility of dielectric determines the use environment of polar and nonpolar capacitors. ③Different performance.Performance and maximization of requirements are the requirements for use. If a metal oxide film capacitor is used for filtering in the power supply part of the TV set, and the capacity and withstand voltage of the capacitor should meet the requirements of filtering, a power supply must be installed in the shell. For a filter, only the polar capacitance can be used, which is irreversible. The positive terminal must be connected to the high potential terminal and the negative terminal to the low potential terminal. Generally, when the electrolytic capacitance is more than 1 microfarad, it is used for coupling, decoupling, power filtering, etc. Most of the nonpolar capacitors are below 1 microfarad, which participates in resonance, coupling, frequency selection, current limiting, etc. Large capacity and high withstand voltage capacitors are usually used for reactive power compensation, motor phase-shifting and frequency conversion power supply phase-shifting. There are many kinds of nonpolar capacitors. ④Different capacityFor capacitors of the same volume, when the medium is different, the capacity is also different. ⑤Different structureWe can use capacitors of any shape without considering the tip discharge. The polar capacitance is usually round, and there are few polar capacitances of square type. There are many shapes of nonpolar capacitors, including tube type, deformed rectangle, sheet type, square type, circular type, combined square type and circular type, and of course there are intangible ones. Here intangible refers to distributed capacitance.The distributed capacitance in HF and IF devices should not be ignored. The function is the same. The main difference is their capacity. Due to the influence of material structure, the capacity of non-polar capacitance is relatively small, generally below 10uF, while the capacity of polar capacitance is usually large. When filtering the power supply, you have to use a polar capacitor of large capacity. Ⅲ SummaryOne of the basic principles of circuit design is to require the designer to fully understand and master the real components. The components used should be standard parts, general parts, and the most common models on the market (the better the versatility of components, the easier the procurement, the larger the supplier's output, and the lower the procurement cost). For the components used in the drawings, if the materials can only be obtained by customization, the cost is certainly not low. If you can't get the customized material, this design is wastepaper. In addition, large capacitance is suitable for filtering low-frequency signals and small capacitance for filtering high-frequency signals. However, decoupling is only one function of capacitance. Different kinds of capacitance have different characteristics and usages. This aspect has a lot to do with experience. It is impossible to achieve it quickly. It can only be accumulated through practice. Ⅳ FAQ1. Which capacitor gives a long-term service: ceramic capacitors or aluminum and tantalum electrolytic capacitors?Electrolytics have a limited lifetime, 10,000 hours at high temps.Tantalums are really good capacitors, until they short out, whenever they feel like it.Ceramics tend to live the longest. 2. Why is aluminum used in electrolytic capacitors?Aluminum has been found to be among ideal materials for electrolytic capacitors due to the following reasons—1) It easily forms a thin oxide layer with a high dielectric constant.2) This layer can be formed in a wide range of thicknesses to suit different applications.3) The aluminum oxide layer can be formed and can withstand high voltages exceeding 400 V. Other materials Tantalum/ Niobium can only take small voltages of below 25 V. 4) Aluminum can be made into foil/ plate / formed into shape. In yesteryears, it was common to use shapes of this metal mechanically formed into different shapes.5) These properties allow high capacitor values for low and high voltages in small size.6) Most amenable to convenient manufacturing processes like winding, punching, forming (oxidation).7) Most abundant material on earth, hence very cheap.There are hardly any other materials that have these properties. 3. What is the role of aluminum electrolytic capacitors?Aluminum electrolytic capacitors are polarized capacitors because of their anodization principle. They can only be operated with DC voltage applied with the correct polarity. Operating the capacitor with the wrong polarity or with AC voltage leads to a short circuit and can destroy the component. 4. What happens if the electrolytic capacitor backward?Electrolytic capacitors are polar by nature and have positive and negative terminals clearly marked. If the polarity is reversed while connecting, the dielectric in the form of an oxide layer is damaged. A heavy current flows, a large amount of heat is generated, and the capacitor is damaged. 5. How do you determine the polarity of the Aluminium electrolytic capacitor?If the case is insulated, you can try applying a small bias voltage (3-5V) to the capacitor in each direction (through a current-limiting resistor of 100K or so) and see which direction allows the least current; this will be the correct polarity of the capacitor. 6. What are aluminum electrolytic capacitors used for?Especially aluminum electrolytic capacitors are used in many applications as decoupling capacitors to filter or bypass undesired biased AC frequencies to the ground or for capacitive coupling of audio AC signals. Then the dielectric is used only for blocking DC. 7. How long do aluminum electrolytic capacitors last?Today's aluminum electrolytic capacitors have a longer shelf life, usually around 2 years, as compared to their predecessors. For aluminum electrolytic capacitors, the changes in ESR, capacitance, and leakage current are caused by the chemical reactions between the aluminum oxide film and the electrolyte. 8. How do you read an electrolytic aluminum capacitor?The value of the capacitor is denoted in picofarads for ceramic, film, and tantalum capacitors, but for aluminum electrolytic capacitors the value is denoted in microfarads. For small values the letter R is used to denote a decimal point, e.g. 0R5 is 0.5, 1R0 is 1.0 and 2R2 is 2.2, etc. 9. How are aluminum electrolytic capacitors made?Aluminum electrolytic capacitors are made by layering the electrolytic paper between the anode and cathode foils and then coiling the result. The process of preparing an electrode facing the etched anode foil surface is extremely difficult. Due to this process, the electrolyte essentially functions as the cathode. 10. What are aluminum capacitors used for?Aluminum electrolytic capacitors (electrolytic) are widely used in power supply applications requiring high capacitance in energy-dense, small-volume packages having very low equivalent series resistance (ESR).
kynix On 2019-12-24
Overview of switchesMain parameter of switchesSwitch SymbolSwitch DiagramWhat is a toggle switch?How does toggle switches work?Video related to toggle switchesFive ways toggle switch wiringCircuit diagram of toggle switchTypes of Toggle SwitchDPDT Toggle SwitchDPST Toggle SwitchSPDT Toggle SwitchSPST Toggle SwitchLED Toggle SwitchAdvantages and Disadvantages of toggle switchesRocker Switches vs Toggle SwitchesToggle Switch ApplicationsToggle Switch FAQ Overview of switchesA switch is a piece of equipment used to stop current flow in a circuit. Simply put, a switch has the power to complete or disrupt an electrical circuit. To turn a device ON and OFF, every electrical and electronic application makes use of at least one switch.Switches are therefore a component of the control system, and control action is impossible without them. A switch has two possible states: completely ON (by shutting its contacts) and completely OFF (by opening its contacts).A switch establishes a closed conduit for the current to flow when its contacts are closed, which causes the load to draw power from the source. As demonstrated in the figure below, no power is used by the load when a switch's contacts are open. Main parameter of switchesSwitches ParametersVoltage ratingThe insulation materials, contact separation, rate of separation, and general safety considerations are some of the variables that affect voltage rating.Current carrying ratingThe electronics switches' current specifications are crucial since they will only be able to transport a particular amount of current through their contacts.Current switching ratingAn electromechanical switch's current switching rating is typically lower than its current carrying rating. The problem is that forming and breaking contacts creates arcing, and the contacts can only handle so much of it before the wear on the contacts significantly limits the operational life.Switch formatFor every electronics circuit design, choosing the appropriate switch format is essential. Toggle switches, slider switches, rotary switches, DIPs, thumbwheels, and many more are among the many various switch formats. Any switch's selection process includes the format.Number of operationsThere is always a tiny degree of wear as the contacts of a switch move across one another to ensure the best resistance is obtained.Contact resistanceThere is a higher contact resistance than there would be if the conductor were continuous because a switch's contacts are not a continuous conductor but can be broken and rebuilt.Power ratingThe maximum power that the switch can manage while working is indicated by its power rating. Overriding this rating may result in an excessive buildup of heat inside the device, which could lead to the switch failing and create a safety issue.Inductive ratingIf not handled properly, any inductance in a circuit will raise the intensity of arcing at the contacts and shorten the life of the switch. This means that once current is flowing, it is challenging to stop since the inductance will produce significant back EMFs when the current is stopped. This is because any inductance in the circuit will oppose the change taking place.Contact typeThere are two different types of contacts used in change-over type electromechanical: Break before make and Make before break. Switch SymbolSwitch Symbol Switch DiagramSwitch Diagram What is a toggle switch?Toggle switches are electrical switches that be opened or closed using a lever or handle that is moved forward and backward. Toggle power switches and joystick switches are other names for these switches. These switches can be used in any electrical application because they are flexible devices.Since switches are typically manipulated manually, the toggle switch, which functions as a straightforward ON/OFF switch in many electrical circuits, is essential. The toggle switch controls the flow of current from the power source to a device or within a device by use of a lever.Toggle Switch How does toggle switches work?The armature switches the contact into position to start or halt an electrical flow when the switch operator pulls the toggle (the actuator). To put it simply, pushing the toggle can turn a gadget on or off. There are two functions that can be used; a momentary function means that the switch is only engaged when the force is applied. An internal spring mechanism forces the armature to return to its initial position in order to accomplish this. A latching toggle switch, in contrast, keeps the state after being depressed until the toggle is depressed once again to release the switch.The basic toggle switch design is as follows, although being available in various forms and configurations. When the toggle is pulled, an armature (a component conducting electrical current) attached to it moves, adding or removing an electrical contact from a circuit and activating or deactivating the circuit.Even though momentary switches also have an associated spring that will draw the actuator back to its starting point if released, the switch will typically stay in place unless manually pushed again. Video related to toggle switchesVideo Description: Add a switch easily to any household electronics item or automotive project easily by watching this short video. Five ways toggle switch wiringStep One: Look at the instruction about the toggle switchesElectrical setups for the many types of equipment that you might wish to install toggle switches on vary substantially. As a result, no single guide is likely to offer a universally applicable solution. The procedures in this section are intended to serve as general guidance for a straightforward on-off (also known as SPST) toggle switch. They should never take precedence over any installation instructions that came with your toggle switch or the appliance you're placing it into.You can look at the below instruction about the toggle switches:Toggle Switches Instruction Step Two: Your device's supply wire should be cutYou must link your toggle switch to the device's power source in order for it to act as an on-off switch. Cut the supply wire for your device with wire cutters at a spot that will make it easiest to route one or both ends of the cable to the switch. Using a wire stripper, remove about 12 inch (1.3 cm) of insulation from each end of the wire.Cut the supply wire Step Three: If the cable does not reach the switch from either end, add a pigtail.A pigtail is a brief wire piece with both ends stripped, often measuring under 6 inches (15 cm). It can be used as a form of "extender" by being attached to cables that aren't quite long enough to reach your toggle switch.Pigtail connetced to switches Step Four: Connect the supply wire to the toggle switchNow that the device's supply wire has been severed, you must insert your toggle switch so that it can control the circuit's current flow in the middle of the break. The kind of toggle switch you have will determine how you should proceed. Step Five: Test your switchWhen your toggle switch is properly wired, carefully reattach the power to the device and check the toggle switch's operation. You can swap out the panel or housing if everything functions as it should. Congratulations! A toggle switch has been fitted successfully. Circuit diagram of toggle switchThe SPDT toggle switch's circuit schematic is displayed below. A 6V battery, two resistors R1 & R3, two LEDs D1 & D3, and a 21236N switch can be used to construct this circuit.Three terminals, including one input and two outputs, make up this switch. Thus, we can acquire two outputs, the first of which comes from pins 2 (COM) and 1 and the second of which comes from pins COM and 3. In three-way circuits, this switch is mostly used to control electrical appliances from two places.The pins 1 and 3 are connected to D1 (an LED) and D2 (an LED), respectively, in the circuit shown above. When pin 1 is toggled, the D1 LED turns on and the D2 LED turns off. In a same manner, when pin 3 is toggled, D2 LED will turn ON and D1 LED will turn OFF. Consequently, we are able to manage two loads using a single SPDT toggle switch.Toggle Switch Circuit Diagram Types of Toggle SwitchThere are four main versions of these switch designs, each of which has a different combination of throws and poles, such as SPDT, SPST, DPDT, and DPST. Poles of these switches are often the distinct power supply controlled by each switch, whereas throws are the various areas the switch can be used, such as ON & OFF.DPDT Toggle SwitchDPST Toggle SwitchSPDT Toggle SwitchSPST Toggle SwitchLED Toggle Switch DPDT Toggle SwitchDouble pole, double throw (DPDT) toggle switches are used to establish or terminate connections between two conductors and two different circuits. There are six terminals on these switches, and terminals 3 and 4 get the necessary power to drive the loads on the other terminals, which are 1, 5, 2, and 6. Four-way or four-position switches are the names given to these switches.DPDT Switches The six terminals of a DPDT toggle switch are. The toggle switch is represented by terminals 3 and 4. The electricity required to drive the loads on terminals 1 and 5, as well as 2 and 6, is supplied to these terminals. Between terminals 1 and 5, terminal 3 can switch. Therefore, terminal 3, which represents the toggle switch, can switch between operating the fan and operating the motor if a fan is connected to terminal 1 and a motor is connected to terminal 5. The same is true for terminal 4, too. Between terminals 2 and 6, terminal 4 can switch. In this case, terminal 4, which acts as the toggle switch, can switch between the heater and the blower if a heater is connected to terminal 2 and a blower is connected to terminal 6.Two input switches on a DPDT switch can each be connected to one of two terminals. It can therefore use two switches to control four distinct circuits or devices.The circuit for a DPDT toggle switch is illustrated below:DPDT Toggle Switch Circuit Diagram DPST Toggle SwitchThe name "DPST" refers to a double-pile single throw switch, which is used to establish or terminate the connection between two circuit conductors inside a single branch circuit. These switches typically have four terminals that can be used to simultaneously connect and disconnect two pairs of terminals.DPST Switches A 30A DPST switch is used in this wiring layout to connect a 240V AC load appliance (such as a dryer or water heater). The hot wires for 240V are immediately linked to the two pole, single throw switch and the load point as it is illustrated because there is no need to wire the neutral wire. The dryer is directly linked to the ground wire. When turned OFF, the DPST switch will cut both hot wires. Similar to that, while in the ON position, it will join both Hot wires.DPST Toggle Switch Circuit Diagram SPDT Toggle SwitchA single conductor connection with any of two additional single conductors can be made or broken using a toggle switch known as an SPDT, or single pole, double throw. These switches typically have three terminals, which are typically utilized in pairs. Any load must be connected to the first terminal in order to power a specific gadget. To power the loads on Terminals 1 and 3, Terminal 2 receives the necessary power, while Terminal 3 is utilized to connect to any load and turn on any device. This switch can therefore power any of two circuits. Three-way switches are another name for these kinds of switches.SPDT Switches Three terminals make up an SPDT toggle switch. Any load can be connected to Terminal 1 in order to power a specific appliance. Furthermore, any load can be connected to terminal 3 to power any device. The power required to power the loads on terminals 1 and 3 is delivered to terminal 2 at this point. A SPDT switch can therefore operate any of two circuits. It can switch between the two circuits so that various gadgets or circuits can be powered with just a flick of the switch. The circuit for an SPDT toggle switch is illustrated below:SPDT Toggle Switch Circuit DiagramWe link our 9-volt DC power source to terminal 2 in this circuit. The toggle switch at terminal 2 allows us to switch between terminals 1 and 3. A fan is attached to Terminal 1. The DC motor does not operate when the switch is flipped to the left (terminal 1). The DC motor turns on when the switch is flipped to the right (terminal 3), but the fan does not. You can see how we can control two distinct circuits or devices with an SPDT switch in this manner. A double throw switch offers two possibilities. SPST Toggle SwitchSPST, which stands for "Single Pole Single Throw," refers to a device with two terminals, such as input and output. These switches function just like an ON/OFF switch. This switch's primary job is to establish or terminate a connection between a single conductor and a single branch circuit. Once this switch is opened, the circuit will be cut off, stopping any current flow through the load. When the switch is closed, current flows through the load in a similar manner.SPST Switches A SPST toggle switch only has 2 terminals, as you can see. The input is on terminal 1. The output will be at the other terminal. Simple ON-OFF switches are what SPST toggle switches do. They interrupt the circuit when open, preventing current from reaching the load. Current can move across a closed circuit and drive the load. You can see that the DC motor may be started or stopped using this circuit simply as an ON/OFF switch. The circuit for an SPST toggle switch is illustrated below:SPST Toggle Switch Circuit Diagram LED Toggle SwitchToggle switches with illumination operate at 12 volts DC and light up to show the status of your circuit. Add some flair to your switch and control panels by using these lit toggle switches. Our assortment is completed by toggle switches with LED tips, duck bills, and longer handles. Red, blue, green, and amber are the available illumination colors. Toggle switches with illumination are available in an ON-OFF, single pole, single throw design. The switches' connections, which consist primarily of power in, power out, and a ground for the indicator light, are 1/4 inch push-on terminals. The fundamentals of how to wire an illuminated toggle switch are demonstrated in our video.You shouldn't have any trouble wiring an LED rocker switch if you pay close attention to where your ground, power, and acc pins are placed, follow the diagram below (which uses Oznium's LED Round Rocker Switch with a recommended mounting hole diameter of 3/4 inch) :LED Toggle Switch Circuit Diagram Advantages and Disadvantages of toggle switchesAdvantagesDisadvantagesUse of these switches with circuit boards is optimal.While using these switches, a clicking sound will be heard.These switches often have a small footprint, are incredibly sturdy, and are very easy to seal.When compared to rocker switches, these are bigger and bulkier.These switches are effective in controlling electricity.It requires a toggle lock washer.There are small and regular sizes of these switches available.Only low voltage circuits can use it.A lever can be used to extend and operate them.-These switches are energy efficient since they utilize less -These switches are very strong.- Rocker Switches vs Toggle SwitchesRocker switches and toggle switches are the two primary categories of maintained switches. The advantage of having a rocker switch is that you can typically add images, symbols, or even writing to the switch's face to make it more personalized. It therefore especially helpful in situations where function communication is required. Switches that can be sealed easily are perfect for usage with circuit boards. indicating increased resilience against water and dust. enhancing the switch's suitability for hostile conditions.Which switch is best for your project will ultimately depend on its design and environmental factors. From a design standpoint, some people favor the toggle switch's appearance, while others like the rocker switch's more common appearance. Your choice will be influenced by the circumstances. A toggle switch, for instance, may be preferable if the product is for the marine industry because of its IP rating. Toggle Switch ApplicationsThese switches give drivers of cars easy access to headlights, comparable controls, and indicator lights.Conveyor belts, residual current devices, and other industrial and electrical equipment employ these (RCDs).These switches are present in home, commercial, and industrial power outlets.It can serve as the primary switch for industrial machinery like conveyors and packaging machines as well as AC equipment.These switches are employed in switching headlights, logic-level programs, automobiles, and aviation control panels, among other things.Toggle switches are utilized as switching circuits in communications, commercial, and industrial equipment. Toggle Switch FAQOverview and Applications of toggle switchAn electronic on/off switch is a toggle switch. The best purpose for toggle switches is to change the status of system settings and functionalities. To allow users to select between two opposed states, toggles may be used in place of two radio buttons or a single checkbox. What are the 4 types of switches?Single pole single throw, single pole double throw, double pole single throw, and double pole double throw are the four primary categories of switches. The differences between toggle and switchSince they both manage states but not in the same way, we must first distinguish between a toggle button and a toggle switch: Toggle button: Represents an action that changes a state. Two (or more) mutually incompatible states or possibilities that can be switched are represented by a toggle switch. Should a toggle switch be on the positive or negative?Never switch the ground return side; always switch the supply side. You can flip both lines if you're using a twin pole switch, but you must keep the ground line to the chassis intact. More corrosion is likely to occur on the negative terminal. What is a toggle switch?In order to switch an electrical circuit, toggle switches include an operating lever that can be moved up and down or left and right. A "toggle" is a little wooden rod that is used in place of buttons to fasten garments.
kynix On 2022-11-15
Introduction Capacitors are the most common passive components used in circuit design. Its function is to block the AC current while pass the DC current, and it also has the function of power storage, and has a good filtering effect, which can output the pulsating signal in a smooth way. The application of capacitors in electronics is very common. Let's talk about the common types of capacitor in circuits and their uses. Basic Introduction to Capacitors Catalog Introduction Ⅰ Types of Capacitors in Use with Models 1.1 Ceramic Capacitors (CC) 1.2 Polyester Capacitor (CL) 1.3 Polystyrene Capacitors (CB) 1.4 Polypropylene Capacitors (CBB) 1.5 Monolithic Ceramic Capacitor (MLCC) 1.6 Mica Capacitors 1.7 Paper Capacitors (CZ) 1.8 Metallized Paper Capacitors (CJ) 1.9 Aluminum Electrolytic Capacitors (CD) 1.10 Tantalum Electrolytic Capacitors (CA) 1.11 Mica Trimmer Capacitors (CY) 1.12 Ceramic Trimmer Capacitors (CC) 1.13 Film Trimmer Capacitors 1.14 Air Variable Capacitor (CB) 1.15 Film Variable Capacitors Ⅱ FAQ Ⅰ Types of Capacitors in Use with Models Virtually all types of capacitor are available as following: 1.1 Ceramic Capacitors (CC) 🔺Material: Use ceramic material as medium, coat a layer of metal (silver) film on its surface, and then sinter at high temperature as an electrode. Ceramic capacitors are divided into Class 1 dielectrics (NPO, CCG); Class 2 dielectrics (X7R, 2X1) and Class 3 dielectrics (Y5V, 2F4).🔺Types: Ceramic capacitors are divided into two types: high-frequency ceramics and low-frequency ceramics. Capacitors with a small positive temperature coefficient of capacitance are used in highly stable oscillation circuits as loop capacitors and pad capacitors. Low-frequency ceramic capacitors are limited to bypassing or blocking DC in circuits with lower operating frequencies, or occasions (including high frequencies) that do not require high stability and loss. Such capacitors should not be used in pulsed circuits because they are prone to breakdown by pulsed voltages.🔺Features: Class 1 have the advantages of small temperature coefficient, high stability, low loss and high withstand voltage. The maximum capacity does not exceed 1000pF, commonly used are CC1, CC2, CC18A, CC11, CCG and other series. Mainly used in high frequency circuits.Class 2 and Class 3 are characterized by high dielectric coefficient, large capacity (up to 0.47μF), small volume, and poor loss and insulation compared to Class 1. 🔺Application Models: Widely used in medium and low frequency circuits for DC blocking, coupling, bypassing and filtering capacitors, and commonly used are CT1, CT2, CT3 and other three series. 1.2 Polyester Capacitor (CL) 🔺Material: A non-polar capacitor with a positive temperature coefficient (that is, when the temperature increases, the capacitance becomes larger) made of polar polyester film as the medium.🔺Advantages: High temperature resistance, high pressure resistance, moisture resistance and cheap price, suitable for bypass capacitors.🔺Application Models: Generally used in medium and low frequency circuits, and commonly used models are CL11, CL21 and other series.🔺Value Identification: Internationally, the withstand voltage value of capacitors is usually represented by letters. The common correspondence between codes and bases is:A: 1.0; B: 1.25; C: 1.6; D: 2.0; E: 2.5; F: 3.15; G4.0;H: 5.0; J: 6.3; K: 8.0; Z: 9.0;The number in front of the letter represents the power of 10, for example, 2A is 102*1.0=100V, 2C is 102*1.6=160V and so on.The letters behind the withstand voltage value represent the capacitance in pF.For example, 823 means the capacity is 82*10^3=82000Pf, 224 means 22*104=220000pf=0.22μF. The last letter means the precision, such as J means the capacity tolerance is ±5% and so on.Typical capacitor identification example: 2A823J is 82000Pf±5%, withstanding voltage 100V. 1.3 Polystyrene Capacitors (CB) 🔺Material: There are two types of foil type and metallized type.🔺Advantages: Foil type has large insulation resistance, low dielectric loss, stable capacity and high precision, but large volume and poor heat resistance; metallized type has good moisture resistance and stability, and can recover after breakdown, also it has advantages of the low insulation resistance and poor high frequency characteristics.🔺Application Models: Generally used in medium and high frequency circuits, and commonly used models are CB10, CB11 (non-sealed foil type), CB14~16 (precision type), CB24, CB25 (non-sealed metallization), CB80 (high pressure type), CB40 (sealed metallization) and other series. In short, they used in various precision measuring instruments, car radios, industrial proximity switches and high-precision digital-to-analog converter circuits. 1.4 Polypropylene Capacitors (CBB) 🔺Material: It is a negative temperature coefficient non-polar capacitor that made of non-polar polypropylene film as the medium. There are two types of unsealed (commonly encapsulated with colored resin paint) and sealed (encapsulated with metal or plastic housing).🔺Advantages: Small loss, stable performance, good insulation and large capacity.🔺Application Models: Generally used in medium and high frequency circuits or as starting capacitors for motors, and commonly used foil polypropylene capacitors include CBB10, CBB11, CBB60, CBB61, etc.; metallized polypropylene capacitors include CBB20, CBB21, and CBB401 series.CBB capacitor series are used in high frequency and high power circuits such as filtering, cross-line, resonance, etc. 1.5 Monolithic Ceramic Capacitor (MLCC) 🔺Material: Multi-layer laminated ultra-miniature capacitors sintered with barium titanate-based ceramic materials.🔺Advantages: It has the advantages of reliable performance, high temperature resistance, moisture resistance, large capacity (range 1pF~1μF), and small leakage current.🔺Disadvantages: Low working voltage (withstand voltage lower than 100V).🔺Application Models: Widely used in resonance, bypass, coupling, filtering, etc, and commonly used are CT4 (low frequency), CT42 (low frequency), CC4 (high frequency), CC42 (high frequency) and other series.🔺ClassificationClass 1It is a temperature-compensated NPO dielectric. The electrical performance of this capacitor is the most stable and basically does not change with temperature, voltage and time. In short, it is an ultra-stable, low-loss capacitor material type and is suitable for high stability and reliability requirements. frequency, UHF and VHF circuits.Class 2It is a high dielectric constant X7R series, so it can make capacitors with larger capacity than NPO dielectrics. This kind of capacitor has relatively stable performance. With the change of temperature, voltage and time, its unique performance does not change significantly. It is a type of stable capacitor material. It is used in DC blocking, coupling, bypass, filter circuit and frequency circuit with high reliability requirements.Class 3It uses Y5V dielectric. This capacitor has a high dielectric constant and is often used in the production of large-capacity capacitors with larger specific capacitance and higher nominal capacity. However, its capacity stability is worse than that of X7R, and its capacity and loss are more sensitive to test conditions such as temperature and voltage. It is mainly used in oscillation, coupling, filtering and bypass circuits in electronic complete machines.Monolithic ceramic capacitors are larger than ordinary ceramic capacitors (10pF~10μF), and have the advantages of large capacitance, small size, high reliability, stable capacitance, high temperature resistance, good insulation, and low cost, so they are widely used. They can not only replace mica capacitors and paper capacitors, but also replace some tantalum capacitors, and are widely used in small and ultra-small electronic devices (such as liquid crystal watches and micro instruments). 1.6 Mica Capacitors 🔺Material: Mica is used as the medium, and a layer of metal film (silver) is sprayed on the surface as the electrode, which is laminated according to the required capacity and then dipped and compressed in the bakelite shell (or ceramic or plastic shell).🔺Advantages: Good stability, small distributed inductance, high precision, low loss, large insulation resistance, good temperature characteristics, that is, good frequency characteristics, high operating voltage (50V~7kV) and so on.🔺Application: It is generally used for signal coupling, bypassing, tuning, etc. in high-frequency circuits. For example, they are common in occasions that require high stability and reliability of capacitors, such as instruments and meters of electronic, power and communication equipment, and are also used in aerospace, aviation, navigation, rockets, satellites, military electronics, and oil exploration equipment. Commonly used ones are CY, CYZ, CYRX and other series. 1.7 Paper Capacitors (CZ) 🔺Material: The thin capacitor special paper is used as the medium, and the aluminum foil or lead foil is used as the electrode.🔺Advantages: The capacitance (100pF~100μF) has a wide working voltage range, and the maximum withstand voltage value can reach 6.3kV.🔺Disadvantages: Large size, low capacity accuracy, large loss, and poor stability.🔺Classification: Paper capacitors are divided into inductive type and non-inductive type according to winding methods. The inductive core is actually a ribbon coil with many turns, so the inductance is large. The non-inductive type is to stagger the electrode foils to both sides of the paper, so that the sides of the foil strips extend out of the paper strips, and then the leads are welded after winding into a cylindrical core. In this way, the coils of the electrode foil are short-circuited with each other, so the inductance is very small. This capacitor can be used at higher frequencies.🔺Application Models: Common ones are CZ11, CZ30, CZ31, CZ32, CZ40, CZ80 and other series. 1.8 Metallized Paper Capacitors (CJ) 🔺Material: Using vacuum evaporation technology, a layer of metal film is evaporated on the paper coated with paint film as an electrode.🔺Advantages: Compared with ordinary paper capacitors, it is small in size, large in capacity, and has strong recovery ability after breakdown, which is an unique characteristic. For common situation, when the paper-dielectric capacitor is broken down, the paper medium is scorched, and the two layers of metal foil are melted together at the breakdown place to form a short circuit. But for metallized paper capacitors, the metal film at the breakdown place evaporates at high temperature, leaving only insulating holes and no short circuit.🔺Application Models: Common ones are CJ10, CJ11 and other series. 1.9 Aluminum Electrolytic Capacitors (CD) 🔺Material: The polar one is made by winding the aluminum foil (positive electrode) with an oxide film and the backing paper impregnated with the electrolyte solution together with the cathode foil lamination. Appearance package has tube type and vertical type. And there is a blue or black plastic cover outside the aluminum shell.🔺Advantages: The capacity range is large, generally 1~10000μF, and the rated working voltage range is 6.3V~450V.Disadvantages: Medium loss, large capacity error (maximum allowable deviation is +100%, -20%), poor high temperature resistance, long storage time and unstable working state.🔺Application: Usually used in DC power circuits or medium and low frequency circuits for filtering, decoupling, signal coupling, time constant setting, and DC blocking. Note that the polarity cannot be reversed when used as a filter capacitor in a DC power supply.Selection: The capacity and withstand voltage marked on the body of the aluminum electrolytic capacitor are very important and are the most basic content for selecting capacitors. In the actual selection of capacitors, a capacitor with a larger capacity should be used for places where the current changes rapidly, but it’s not always good. First, the larger the capacity, the higher the cost and volume. In addition, the larger the capacitor, the higher the charging current. The bigger it is, the longer the charging time will be. These are all to be considered in practical application selection. 1.10 Tantalum Electrolytic Capacitors (CA) 🔺Material: There are two forms:1) The foil type tantalum electrolytic capacitor adopts a winding core inside, the negative electrode is liquid electrolyte, and the medium is oxidized tantalum. Common models are CA30, CA31, CA35, CAk35 series.2) The tantalum powder sintered positive electrode is sintered with very fine tantalum powder blocks. Packaging comes in many forms. Widely used models include CA41, CA42, CA42H, CA49, CA70 (non-polar) and other series.🔺Advantages:1) Small SizeSince capacitors use tantalum powder with very fine particles, and the dielectric constant ε of the tantalum oxide film is 17 higher than that of the aluminum oxide film, the capacitance per unit volume of the tantalum capacitor is large.2) Wide Operating Temperature RangeGenerally, tantalum electrolytic capacitors can work normally under the temperature of -50℃~100℃. Although aluminum electrolytic capacitors can also work in this range, their electrical performance is far inferior to that of them.3) Long Life, High Insulation Resistance and Small Leakage CurrentThe tantalum oxide film dielectric in tantalum electrolytic capacitors is not only resistant to corrosion, but also maintains good performance for a long time.4) Good Impedance Frequency CharacteristicsFor capacitors with poor frequency characteristics, when the operating frequency is high, the capacitance drops significantly, and the loss (tgδ) also rises sharply. But solid electrolytic capacitors can work above 50kHz. As the frequency increases, the capacity of capacitors also decreases, but the decrease is small. Some data show that the capacity decreases by less than 20% when working at 10kHz, while the capacity of aluminum electrolytic capacitors decreases by 40%.5) High ReliabilityThe chemical properties of the tantalum oxide film are stable, and because the tantalum anode substrate Ta2O5 is resistant to strong acids and alkalis, it can use solid or acid-containing liquid electrolytes with low resistivity, which makes the loss of tantalum electrolysis smaller than that of aluminum electrolytic capacitors, and the temperature stability is good.🔺Disadvantages: High production cost and low pressure resistance.🔺Application: Widely used in various medium and low frequency circuits and time constant setting circuits in communications, aerospace, military and household appliances.With the properties of storing electricity, charging and discharging, etc, they are mainly used in filtering, energy storage and conversion, mark bypass, coupling and decoupling, and time constant components. Pay attention to its performance characteristics in application, and correct use will help to give full play to its functions, such as considering the working environment of the product and its heating temperature, and taking measures such as derating, if it is used improperly, it will affect the service life of the product. A variable capacitor is a capacitor whose capacitance can be adjusted within a certain range. When the relative effective area between the pole pieces or the distance between the pieces changes, its capacitance changes accordingly. Usually used as a tuning capacitor in a radio receiving circuit. Here are several types as following: 1.11 Mica Trimmer Capacitors (CY) 🔺Material: It consists of a fixed piece and a moving piece. The fixed piece is a metal piece, and a layer of mica flakes is the most medium on its surface. The moving piece is an elastic copper or aluminum piece. Adjust the moving piece and the fixed piece by adjusting the screws on the moving piece, then the distance between the slices changes the capacitance. There are single trimmers and double trimmers.🔺Advantages: The capacitance can be adjusted repeatedly.🔺Application: Used in transistor radios, electronic instruments, and electronic equipment. 1.12 Ceramic Trimmer Capacitors (CC) 🔺Material: Ceramic is used as the medium, and the semicircular silver layer is plated on both the moving plate and the stator. By rotating the moving plate to change the relative position between the two silver plates, the size of the capacitance can be changed.🔺Advantages: Small size, can be adjusted repeatedly, easy to use.🔺Application: Used in transistor radios, electronic instruments, and electronic equipment. 1.13 Film Trimmer Capacitors 🔺Material: Use organic plastic film as a medium, that is, add it between the moving piece and the fixed piece. Adjust the screw on the moving piece, and make the moving piece rotate to change the capacity. Film trimmer capacitors are generally divided into double trimmers and quadruple trimmers. Some sealed double-connected or four-connected variable capacitors have their own thin-film trimmer capacitors, which are installed on the top of the casing, making it easier to use and adjust.🔺Advantages: With small size, light weight, it can be adjusted repeatedly and is easy to use.🔺Application: Used in transistor radios, electronic instruments, and electronic equipment. 1.14 Air Variable Capacitor (CB) 🔺Material: The electrode consists of two sets of metal sheets. One set is the fixed piece, the other is the moving piece, and the air is used as the medium between them. When the rotor is rotated to make it all screw into the stator, its capacitance is the largest, on the contrary, when the rotor is fully screwed out of the stator, the capacitance is the smallest. Air variable capacitors are divided into single-connection and double-connection.🔺Advantages: It is easy to adjust, with stable performance, and not easy to wear.🔺Disadvantage: Bulky.🔺Application: Used in radios, electronic instruments, high-frequency signal generators, and communication electronic equipment. 1.15 Film Variable Capacitors 🔺Material: A plastic film is added between the moving piece and the stator as a medium, and the shell is encapsulated by transparent or translucent plastic, so it is also called a sealed double-connected and four-connected variable capacitor.🔺Advantages: Small size and light weight.🔺Disadvantages: It is easy to wear.🔺Application: Single connection is mainly used in simple radios or electronic instruments; double connection is used in transistor radios and electronic instruments and electronic equipment; quadruple connection is commonly used in AF/FM multi-band radios. Ⅱ FAQ 1. What are different types of capacitors?Types of CapacitorsCeramic Capacitors.Film Capacitors.Power Film Capacitors.Electrolytic Capacitors.Ceramic capacitors.Film capacitors.Paper capacitors.Electrolytic capacitors. 2. What are the 2 types of capacitor?Capacitors are divided into two mechanical groups: Fixed capacitors with fixed capacitance values and variable capacitors with variable (trimmer) or adjustable (tunable) capacitance values. The most important group is the fixed capacitors. Many got their names from the dielectric. 3. What is the difference between different types of capacitors?The primary difference between the two is that one uses paper while the other uses plastic. Plastic film capacitors hold an advantage over impregnated-paper types in that they have smaller tolerances, high reliability, a long service life, and can continue operating sufficiently while in high temperatures. 4. What devices use capacitor?Capacitors are essential components in a wide range of electronic systems including smart phones, household electric appliances, electric vehicles, and medical devices to name a few. 5. What are capacitors used for?Capacitor, device for storing electrical energy, consisting of two conductors in close proximity and insulated from each other. 6. What is capacitor and its applications?Capacitor is a basic storage device to store electrical charges and release it as it is required by the circuit. Capacitors are widely used in electronic circuits to perform variety of tasks, such as smoothing, filtering, bypassing etc…. One type of capacitor may not be suitable for all applications. 7. Where are capacitors used and why?Capacitors are widely used in electronic circuits for blocking direct current while allowing alternating current to pass. In analog filter networks, they smooth the output of power supplies. 8. How is capacitor used in real life?The most common use for capacitors is energy storage. Additional uses include power conditioning, signal coupling or decoupling, electronic noise filtering, and remote sensing. Because of its varied applications, capacitors are used in a wide range of industries and have become a vital part of everyday life. 9. What are capacitors used for list 5 applications?Applications of capacitors1) Energy storage.2) Pulsed power and weapons.3) Power conditioning.4) Power factor correction.5) Suppression and coupling. 5.1 Signal coupling. 5.2 Decoupling.6) Motor starters. 6.1 Signal processing. 6.2 Tuned circuits.7) Sensing. 7.1 Changing the dielectric.8) Oscillators. 10. What are the advantages of capacitors?Advantages of capacitors include a very high cycle life and charge rates that nearly match discharge rates. Also, supercapacitors can be “floated” for long lengths of time. This means that they will hold their charge (potential energy) for a long period without a large residual decay. 11. Which capacitor is used for high frequency?Mica capacitors have low resistive and inductive components associated with it. Hence, they have high Q factor and because of high Q factor their characteristics are mostly frequency independent, which allows this capacitor to work at high frequency. 12. Where are capacitors used examples?They are used to store energy and then release it when needed.Case 1: Camera flash. A camera flash requires a lot of energy in a short space of time in order to produce a bright enough flash. ...Case 2: Computer emergency shutdown. If a computer loses power it will not be able to shutdown safely. ...Case 3: AC to DC conversion.
Ivy On 2022-03-01
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