The Kynix Blog

Overview: Transportation electrification began with small electric vehicles and gradually entered into medium-duty and heavy-duty vehicle electrification. In this article, we will understand the importance of commercial vehicle electrification and the challenges ahead. Significance of Commercial Vehicles Electrification Global climate change has resulted from human-caused greenhouse gas (GHG) emissions, which have raised the earth's temperature over the past century. The 2016 Paris Agreement sought to reduce global GHG emissions in order to keep the average global warming within two °C above pre-industrial temperatures in order to combat this threat from climate change. The transportation industry, which produces nearly 25% of the world's CO2 emissions, is one of the biggest sources of GHG emissions. Road vehicles account for nearly 75% of all CO2 emissions in the transportation industry among all modes of transportation. Therefore, a crucial step in reducing direct CO2 emissions is the electrification of road transportation. Many governments have therefore established transitional plans to electrify their transportation sector by 2050. Around 10 million electric vehicles (EVs) were in use worldwide as of the end of 2020, with battery electric vehicles making up two-thirds of this total. These EVs are predominantly light passenger cars. Challenges in Commercial Vehicles Electrification Nearly 40% of the world's road transportation sector's CO2 emissions in 2015 came from commercial vehicles, and under the "business as usual" scenario, those emissions are expected to at least double between 2015 and 2050. Therefore, the electrification of commercial vehicles is a crucial research area because it offers a promising chance to significantly reduce these emissions. Due to the small size of electric vehicle batteries, their low mileage, and the lack of public charging infrastructure, the majority of studies on electrifying commercial vehicles have concentrated on the hybridization of these vehicles.  Light-duty trucks (LDTs), which have been successfully electrified without significantly altering travel habits, have been the primary focus of the initial deployment of zero-emission commercial electric vehicles (CEVs), including electric trucks (ETs). Heavy-duty truck (HDT) deployment is in the pilot stage, whereas the deployment of medium-duty trucks (MDT) is still in the early stages. According to recent studies, there have been around 2,50,000 light-duty commercial electric vehicle sales, including trucks, with a stock of close to 31,000 medium- and heavy-duty vehicles. When compared to light passenger vehicles, commercial electric vehicle adoption has lagged, which has been attributed to the unsatisfactory policies implemented in this sector. With the availability of suitable charging infrastructure that meets the charging needs of these vehicles, the possibility of electrifying commercial vehicles grows. Commercial vehicle drivers are unlikely to switch to electric vehicles if the charging process is more challenging, uncertain, and time-consuming. However, as can be seen from Table 1, there are a variety of uses for commercial vehicles, which also affects the average load, trip length, and daily mileage of these vehicles. Furthermore, compared to passenger vehicles, the operational schedules of commercial electric vehicles can affect how quickly these vehicles charge up at charging infrastructure. Table 1. Different applications of commercial vehicles. Source: IEEE AccessVMTi refers to Vehicle Miles Travelled,PTOii refers to Power Take-Off,Percentageiii The percentage of the truck population by vocations depends on California truck population. Recent Advancements in Commercial Vehicles Electrification  In contrast to diesel and alternative fuel trucks, however, recent advancements in lithium battery technology have made electric trucks both technically and financially feasible. Existing studies have examined the potential advantages of ETs over diesel trucks over a vehicle's lifetime. These studies have found that, despite the high upfront costs of ETs, they can perform at least as well as diesel trucks over their entire lifecycle, particularly if the latter have long battery lives and high annual mileage. Moreover, the use of ETs, particularly MDTs, and HDTs, has increased as a result of regulations and government incentives encouraging the use of zero-emission vehicles. With battery sizes ranging from 300 kWh to roughly 990 kWh, a number of truck manufacturers, including DAF, Daimler, MAN, Navistar, Nikola, PACCAR, Volkswagen, Volvo, Tesla Inc., and Thor Trucks, have made significant plans to electrify their MDTs and HDTs. Due to their short-range needs and compact batteries, MDTs have drawn the most attention from these announcements regarding electrification. All of the announcements have a model for medium-duty trucks, and some manufacturers, like Daimler and BYD, have already released their commercial trucks for certain markets. In their announcements, some manufacturers, including Navistar, Volkswagen, Thor Trucks, Freightliner, and Tesla Inc., have mentioned the production of HDTs.  On the other hand, a lot of businesses have started incorporating ETs into their fleets or have made an announcement regarding their procurement of ETs. For instance, Walmart Inc. reported 45 class 8 Tesla Semi HDT pre-orders for the coming year. Similar orders for electric delivery trucks were made by Amazon and Rivian in 2019, and Anheuser-Busch announced plans to use 21 HDTs from BYD in California by the end of the year. In general, commercial vehicles, such as trucks, can be divided into three groups based on their gross vehicle weight (GVW). LDTs fall into this category if their GVW is less than 3.5 tonnes (t), MDTs fall into this category if their GVW is between 3.5t and 15t, and HDTs fall into this category if their GVW is above 15t. Each category has a wide range of vehicle types appropriate for their range of occupational operations, such as long-haul freight and garbage collection trucks.  Due to policies encouraging the adoption of zero-emission vehicles and advancements in battery technology, the electrification of MDTs and HDTs has been increasingly adopted in recent years. MDT models with battery bank capacities ranging from 48.5 kWh to about 350 kWh and an estimated range of up to 400 km have been produced by numerous truck manufacturers. Many models of HDTs with battery bank capacities between 120 kWh and 1000 kWh to cover an estimated range of up to 800 km have been introduced or produced. Table 2 lists the specifications of some MDTs and HDTs that are currently advertised or reported. Table 2. Specification of some commercial electric vehicles. Source: IEEE Access The estimated range of CEVs and the availability of appropriate charging infrastructure determine whether or not they can be used to cover the daily travel distance of commercial vehicles. According to surveys, most medium-duty commercial vehicles travel an average daily distance of 80 km to 250 km, while heavy-duty commercial vehicles travel an average daily distance of up to 700 km. As a result, at locations where they park overnight or in between shifts, the reported range of medium-duty CEVs can cover a sizable portion of the daily travel distance with just one charging event per day.  However, some medium- and heavy-duty CEVs require high charging rates to be met in a single charging event over the times they are parked because of high charging requirements (such as long-haul operation, multiple-shift operation, etc.). A high percentage of the daily travel distance is covered by multiple charging events per day at various locations along commercial vehicles' routes due to the constrained capacity of some electrical power infrastructure, which restricts the charging rate of charging infrastructure. Therefore, the number of times a CEV may need to be charged each day will depend on the daily mileage of commercial vehicles, the CEV's estimated range, and the infrastructure's charging rate. Summarizing With Key Points: Some of the takeaways from the article are as follows: Transportation emits nearly 25% of the world's CO2 and GHGs. Thus, many governments have transitional plans to electrify transportation by 2050. As of 2020, there were 10 million electric vehicles (EVs), two-thirds of which were battery-electric. Light passenger cars dominate these EVs.Most studies on electrifying commercial vehicles have focused on hybridization because electric vehicle batteries are small, have low mileage, and lack charging infrastructure.If charging is difficult, uncertain, and time-consuming, commercial vehicle drivers will not switch to electrifying their vehicles.Recently, MDTs and HDTs have been electrified due to policies encouraging zero-emission vehicles and advances in battery technology.  This blog post is part of a full research article from IEEE Access.*******************************************************************************************************************************************

Catalog IntroductionComponentsArduino Code Introduction The idea of this project is to create an Arduino based home security alarm system that can be used to monitor and control the various appliances in the house. The main purpose of the system is to detect any unusual activity and notify the user about it in an efficient manner. The system will also use a web server to push notifications to mobile devices such as smartphones and tablets. The project consists of an Arduino Uno board connected to a Debounce shield which contains a piezo buzzer, LED, power supply and other components necessary for interfacing with Arduino Uno board. A passive infrared sensor, or PIR, is a Pyroelectric device that senses motion. For this reason, it is sometimes referred to as a motion detecting sensor. It may be able to detect motion by detecting variations in the infrared levels emitted by nearby objects. This gadget is a basic motion-activated alarm. Its brain is an Arduino microcontroller. It is connected to a PIR motion sensor, a buzzer, a resistor, and two external connectors. The system is very portable because it is entirely battery-powered. As soon as you get the code, you may link all of the external components. This is the easiest thing to do with a breadboard. To check everything out, you can create bogus connections.  The whole system Is powered by 12V DC power supply which powers all other components except Arduino Uno board itself. The MCU receives digital commands from Arduino Uno through SCI interface and sends appropriate analog or digital signals on its pin according to the command received by it. This project has been inspired by many previous projects that use Arduino boards for controlling various electronic devices such as lamps, lights etc., but this project focuses more on controlling various appliances. The Arduino Uno Is based on the ATmega328 chip, which has built-in USB support for serial communications. It also has a built-in 5V power regulator that allows it to be powered directly from the USB connection or from a battery. Components 1Arduino2Motion Sensor3LED’s4Buzzer5LCD Module Arduino Code#include  <LiquidCrystal.h>   int ledPin = 13;                int inputPin = 7;               int pirState = LOW;             int val = 0;                    int pinSpeaker = 10;           LiquidCrystal lcd(12, 11, 5, 4, 3, 2);                           void setup() {  pinMode(ledPin, OUTPUT);  pinMode(pinSpeaker, OUTPUT);  Serial.begin(9600);  lcd.begin(16, 2);  lcd.setCursor(2, 0);                                              lcd.print("P.I.R Motion");                                        lcd.setCursor(5, 1);                                             lcd.print("Sensor");                                              delay(4000);  lcd.clear();  lcd.setCursor(2, 0);                                              lcd.print("Displaying");                                       lcd.setCursor(2, 1);                                              lcd.print("A");                                         delay(5000);                                                      lcd.clear();                                                    lcd.setCursor(0, 0);      lcd.print("Processing Data.");      delay(3000);      lcd.clear();      lcd.setCursor(3, 0);      lcd.print("Waiting For");      lcd.setCursor(3, 1);      lcd.print("Motion....");     }void loop(){  val = digitalRead(inputPin);  if (val == HIGH) {                digitalWrite(ledPin, HIGH);      playTone(300, 300);    delay(150);        if (pirState == LOW) {      Serial.println("Motion detected!");      lcd.clear() ;      lcd.setCursor(0, 0);                                                 lcd.print("Motion Detected!");             pirState = HIGH;    }  } else {      digitalWrite(ledPin, LOW);      playTone(0, 0);      delay(300);         if (pirState == HIGH){            Serial.println("Motion ended!");      lcd.clear() ;      lcd.setCursor(3, 0);      lcd.print("Waiting For");      lcd.setCursor(3, 1);      lcd.print("Motion....");            pirState = LOW;    }  }}// duration in mSecs, frequency in hertzvoid playTone(long duration, int freq) {    duration *= 1000;    int period = (1.0 / freq) * 100000;    long elapsed_time = 0;    while (elapsed_time < duration) {        digitalWrite(pinSpeaker,HIGH);        delayMicroseconds(period / 2);        digitalWrite(pinSpeaker, LOW);        delayMicroseconds(period / 2);        elapsed_time += (period);    }} 

Catalog PurposeHardwareSofowareConclusion Smart homes have been a popular topic for several years now. With the rapid development of technology, it has become easier and more affordable for people to make their homes smart. One of the simplest and most useful smart home projects is a smart light. In this article, we'll show you how to use a Raspberry Pi to make a smart light. A smart light turns on automatically when you enter the room and turns off when you leave, saving energy and providing a more convenient experience. This project is a great way to learn about the Raspberry Pi and how to control it using Python, making it a great choice for both beginners and experienced makers. Purpose The purpose of this project is to create a smart light that is convenient, energy-efficient, and saves you time. This smart light can be controlled using motion detection, so when you enter the room, the light will turn on automatically, and when you leave, the light will turn off. This feature will save energy, as you don't have to manually turn the light off, and it will also provide a more comfortable experience. Hardware Building a smart light using a Raspberry Pi involves connecting several hardware components together to form a complete system. The process involves connecting a PIR (Passive Infrared) sensor to the Raspberry Pi, which detects motion in the room. The Raspberry Pi is then connected to a relay module, which acts as an intermediary between the PIR sensor and the  LED light. Finally, the LED light is connected to the relay module to provide illumination. The following is a list of the hardware components required for this project: 1. Raspberry Pi - a credit-card sized computer that can be used for a variety of projects. 2. PIR sensor - used to detect motion in the room and trigger the relay module to turn on oroff the LED light. 3. Relay module - used to switch the LED light on and off based on the input from the PIR sensor. 4. LED light - used to provide illumination in the room. 5. Power supply for the Raspberry Pi - used to power the Raspberry Pi and its components. 6. Jumper wires - used to connect the components together. 7. Bread board - used to create a prototype circuit for the project. Purchase on Kynix1Raspberry Pi2PIR sensor3Relay module4LED light5Power supply6Jumper wires7Bread board It is important to use a relay module for this project because the Raspberry Pi does not have enough power to directly control the LED light. The relay module provides an isolated circuit between the Raspberry Pi and the LED light, making it safe to use and preventing damage to the Raspberry Pi. The use of a breadboard allows you to easily modify and test the circuit, making it easier to troubleshoot any problems that may arise. Below is the description of circuit diagram:1. Connect the PIR sensor to the Raspberry Pi. The PIR sensor has three pins: VCC (power), GND (ground), and OUT (output). Connect the VCC pin to the 5V pin on the Raspberry Pi, the GND pin to a GND pin on the Raspberry Pi, and the OUT pin to a GPIO pin on the Raspberry Pi (for example, GPIO 18).2. Connect the LED light to the Raspberry Pi. The LED light has two pins: anode (+) and cathode (-). Connect the anode to a GPIO pin on the Raspberry Pi (for example, GPIO 23) and the cathode to a GND pin on the Raspberry Pi.3. Connect a resistor to the anode of the LED light. This resistor is used to limit the current flowing through the LED and protect it from damage. The value of the resistor will depend on the forward voltage and forward current of the LED, which are specified by the manufacturer. A common value is 220 ohms.4. Connect the Raspberry Pi to a power source, such as a micro USB cable, to provide power to the Raspberry Pi and all of the connected components. Software In order to turn your Raspberry Pi into a smart light, you will need to write code using Python and the RPi. GPIO library. This library provides an easy way to control the GPIO pins on the Raspberry Pi, allowing you to read from sensors and control other components like the relay module and LED light. Before writing the code, you need to install the RPi. GPIO library on your Raspberry Pi. You can do this by running the following command in the terminal:sudo apt-get install python-rpi.gpio Alternatively, you can install the library using pip by running the following command:pip install RPi.GPIO Once the library is installed, you can start writing your code. The following is an example of the code needed to create a smart light using a Raspberry Pi:1. Import the RPi.GPIO library:            import RPi.GPIO as GPIO                                                     2. Set the GPIO pin mode:           GPIO.setmode(GPIO.BCM)                                                      3. Set the GPIO pin for the PIR sensor and relay module as inputs:            GPIO.setup(PIR_PIN, GPIO.IN)                                                           GPIO.setup(RELAY_PIN, GPIO.OUT)                                             4. Createaloop to check the PIR sensor and turn the relay module and LED light on or off:            while True:                                                                                  if  GPIO.input(PIR_PIN):                                                                      GPIO.output(RELAY_PIN, True)                                                             print("Motion detected, turning on light")                                          else:                                                                                   GPIO.output(RELAY_PIN, False)                                                       print("No motion detected, turning off light")                     5. Clean up the GPIO pins before exiting the program:              GPIO.cleanup()                                                              This code uses the RPi. GPIO library to check the PIR sensor for motion and turn the relay module and LED light on or off accordingly. The code uses a while loop to continuously check the PIR sensor and update the status of the relay module and LED light. The GPIO.cleanup() function is used to clean up the GPIO pins before the program exits, preventing any potential conflicts with other programs that may be using the same pins. Conclusion In this article, we have explored how to use a Raspberry Pi to create a smart light that turns on and off based on motion detection. We have discussed the hardware required, including a Raspberry Pi, PIR sensor, relay module, and LED light. We also provided a code example using the RPi. GPIO library to check the PIR sensor and control the relay module and LED light. Building a smart light using a Raspberry Pi is a simple and cost-effective project that can be completed in a few hours. It provides a great introduction to using the Raspberry Pi and the RPi.GPIO library and can be easily modified to meet your specific needs. Whether you are looking to automate your home or just interested in learning more about the Raspberry Pi, building a smart light is a great starting point.

The goal of this project is to design and build an automated paint mixer that can accurately and efficiently mix various types of paint to a consistent and predetermined color and consistency. This machine will be able to handle a wide range of paint types, including water-based, oil-based, and specialty paints, and will be able to mix small and large quantities of paint with precise control. Mixing paint by hand can be a time-consuming and labor-intensive process and achieving a consistent color and consistency can be difficult and require significant trial and error. In addition, the manual process is prone to errors and inconsistencies, which can lead to wasted materials and costly rework. An automated paint mixer is a machine that is used to mix different types of paint in a precise and consistent manner. The main components of an automated paint mixer include a linear screw actuator, a mixer, a controller (such as an Arduino, PLC, or other type of controller), a DC gear motor, a DC pump, a flow sensor, a relay module, an impeller, and a webcam (ESP-CAM).   Materials1Controller (Arduino, PLC, ARM controller, Raspberry Pi)2DC Gear Motor3Photoelectric IR Sensor4DC Pump5Flow Sensor6Esp Cam7Linear Screw Actuator8Mixer Actuator (Impeller)9Conveyor Belt The linear screw actuator is a type of mechanical device that converts rotary motion into linear motion. It consists of a screw that is turned by a motor, which drives a nut along the length of the screw. In an automated paint mixer, the linear screw actuator is used to move the mixer up and down, allowing it to mix the paint thoroughly. The mixer is the component that actually mixes the paint. It can be a simple paddle mixer, or it may be a more complex device with multiple blades or other mixing elements. The mixer is typically powered by the DC gear motor, which is a type of electric motor that is commonly used in automated paint mixers because of its high torque and low speed. The controller is the "brain" of the automated paint mixer. It receives input from the various sensors on the machine (such as the flow sensor) and uses this information to control the various components of the mixer (such as the DC pump and the linear screw actuator). The controller can be an Arduino, a PLC, or any other type of device that can receive input and controlling output. The DC pump is used to move the paint from one location to another within the mixer. It is typically powered by the DC gear motor and is controlled by the controller. The flow sensor is a device that measures the flow rate of the paint as it is being pumped. This information is used by the controller to ensure that the correct amount of paint is being mixed.  The relay module is a device that is used to control the flow of electricity to the various components of the automated paint mixer. It is activated by the controller and allows the controller to turn different components on and off as needed. The impeller is a component that is used to mix the paint more thoroughly. It is a type of rotor with blades that is placed inside the mixer and is rotated by the DC gear motor. The impeller helps to break up any clumps or lumps in the paint, ensuring that it is fully mixed. Finally, the ESP-CAM (or webcam) is a camera that is used to monitor the mixing process. It is connected to the controller and can be used to view the mixer remotely, allowing for easy monitoring of the mixing process. Overall, an automated paint mixer is a complex and sophisticated machine that is designed to mix different types of paint in a precise and consistent manner. Its various components work together to ensure that the paint is mixed properly and that the final product is of the highest quality.

Catalog IntroductionHardware componentsSoftware componentsHardware SpecificationsSoftware SpecificationsReference codeConclusionIntroductionParking is a major issue in today's contemporary, congested cities. Simply put, there are too many vehicles on the road and not enough parking spaces. As a result, efficient parking management solutions are increasingly necessary. As a result, we demonstrate how to set up a parking management system based on IOT that promotes efficient parking space utilization. To demonstrate the concept, we use IR sensors to detect parking space occupancy and a DC motor to simulate gate opening motors. We presently use an AVR microcontroller and a Wi-Fi modem to link the system to the internet. We use IOTGecko for internet connectivity and GUI design for IOT administration. The system determines whether parking spaces are occupied using IR sensors. To open the gate automatically when a car is detected on the fence, it also uses IR technology. The technology reads the number of parking spaces that are available and updates data with the cloud server to enable online parking slot availability checks. Customers can now check the availability of parking spaces online from any place to find parking without fuss. As a result, the system gives users access to a powerful IOT-based parking management system while also helping cities find a solution to their parking issues. An IoT (Internet of Things) based smart parking system is a technology solution that utilizes sensors, cameras, and other IoT devices to streamline the process of finding and reserving parking spots in each area. These systems can be deployed in a variety of settings, including urban areas, airports, shopping malls, and university campuses, to name a few. One of the primary benefits of an IoT based smart parking system is that it helps to reduce the time and frustration associated with finding a parking spot. By providing real-time information about the availability of parking spaces, these systems can direct drivers to open spots, saving them the hassle of driving around aimlessly searching for a place to park. The cameras in the system can also be used to monitor and enforce parking regulations, such as time limits and restricted areas.Hardware componentsThe hardware components of an IoT based smart parking system include sensors, such as infrared (IR) sensors, which are used to detect the presence of a vehicle in a particular parking space. The system may also include DC motors, which can be used to move physical barriers or gates to allow or block access to parking spaces. Other hardware components include an AT mega microcontroller, which serves as the brain of the system and coordinates all the other components, an LCD display, which can be used to provide information to drivers, and a power supply, which powers all the system's components. Software componentsIn addition to hardware components, an IoT based smart parking system also requires a robust and reliable network infrastructure. This may include a Wi-Fi modem, which allows the system to connect to the internet and transmit and receive data in real-time. The system may also include various ICs (integrated circuits), resistors, capacitors, LEDs (light emitting diodes), and diodes, which are used to control and regulate the flow of electricity within the system. The software components of an IoT based smart parking system are equally important. These may include the Arduino compiler, a popular tool for programming microcontrollers, and the C programming language, which is often used to write the code that runs on these systems. Another software tool that may be used is IOTGecko, a platform for building and deploying IoT applications. One of the challenges of implementing an IoT based smart parking system is the cost of the initial investment, as these systems can be expensive to implement. However, many organizations that have implemented these systems have found that the long-term cost savings and benefits of these systems far outweigh the upfront costs.Hardware Specifications1IR sensors2DC Servo motors3AT mega Microcontroller4LCD Display5Power Supply6Wi-Fi Modem/Wi-Fi Module7Resistors8Capacitors9LED’s10Diodes Software SpecificationsArduino CompilerMC Programming Language: CIOTGeckoReference codeThe code is for reference only:  ConclusionIn conclusion, an IoT based smart parking system is a technology solution that utilizes sensors, cameras, and other IoT devices to streamline the process of finding and reserving parking spots. These systems can help to reduce the time and frustration associated with finding a parking spot, improve traffic flow, reduce congestion, and lower the overall cost of parking. While implementing these systems can be challenging, the long-term benefits often make it a worthwhile investment.

CatalogⅠ What are Tantalum Capacitors? Ⅱ Tantalum Capacitors Specifications   2.1 Form Factor  2.2 Standards  2.3 CapacitanceⅢ SMD Tantalum Capacitors 6Ⅳ Applications for Tantalum Capacitors Ⅵ Tantalum vs. Ceramic Capacitor Testing   6.1 Tantalum vs. Ceramic Capacitor IR Life Test   6.2 Tantalum vs. Ceramic Comparative Testing Ⅶ Why Use Tantalum Capacitors in Your PCB Design? Ⅰ What are Tantalum Capacitors?Tantalum capacitors are an electrolytic capacitor subtype. They are composed of tantalum metal, which serves as an anode, a layer of oxide that serves as a dielectric, and a conductive cathode. Tantalum allows for the formation of a very thin dielectric layer. As a result, the capacitance value per volume is higher, the frequency characteristics are superior to many other types of capacitors, and the stability over time is excellent. Tantalum capacitors are generally polarized, which means they can only be connected to a DC supply if the terminal polarity is correct. The disadvantage of using tantalum capacitors is their unfavorable failure mode, which can result in thermal runaways, fires, and small explosions. However, this can be avoided by using external failsafe devices such as current limiters or thermal fuses. Tantalum capacitors can now be found in various circuits, including laptops, the automotive industry, cell phones, and others, most commonly as surface-mounted devices. Surface-mount tantalum capacitors take up much less space on the printed circuit board and allow higher packing densities.A cutaway view of a solid tantalum capacitor is shown in the image below. It's worth noting how thin the coatings around the tantalum core are (manganese dioxide cathode, carbon, silver paint).Solid Tantalum Capacitor Cutaway ViewWet tantalum (electrolytic) capacitors differ from solid tantalum capacitors in that a semi-liquid electrolyte paste serves as a second electrode; these devices are similar to solid aluminum anode aluminum electrolytic capacitors. Electrolytic capacitors have very high capacitance values in general, but due to the required polarity, they are unsuitable for AC power applications; however, they are widely used in DC power supplies. Tantalum capacitors have a longer shelf life, higher temperature resistance, and higher capacitance values than aluminum electrolytic devices, but they are more susceptible to damage from constant voltages as low as 1.5 V. A cutaway view of a wet tantalum capacitor is depicted in the diagram below.Wet Tantalum Capacitor Cutaway ViewⅡ Tantalum Capacitors Specifications2.1 Form FactorTantalum capacitors are typically available in two configurations: leaded (or through-hole) and surface mount (SMT).Long wire leads on leaded capacitors are soldered to a PCB to form an electrical connection. These devices employ through-hole technology (THT), which allows for strong mechanical connections. THT capacitors must be relatively large and have been largely replaced by surface mount products.Surface mount (or chip) capacitors are attached to the top of a PCB with very short leads, flat contacts, or other types of termination. SMT devices are smaller and less expensive to produce than their older THT counterparts.A THT (left) and SMT capacitor2.2 StandardsTantalum capacitors may be manufactured to one or more various standards, including:EIA 535 (series)BS/DIN EN 130201BS EN 60384-24MIL PRF 390062.3 CapacitanceTwo related formulas can be used to calculate the amount of charge on the plates or the maximum capacitance of the device.Capacitance is calculated as:where:C = capacitanceQ = chargeV = voltageIf the applied voltage and capacitance values are known, we can also find the charge by rearranging this formula:Capacitance can also be calculated in relation to a capacitor's geometry:where:C = capacitanceΕ = permittivity of dielectricA = plate aread = distance between platesThis equation demonstrates that capacitance is independent of applied voltage and charge and is only a function of the geometry and dielectric material of the device.Farads are extremely large units used to measure capacitance. The majority of capacitors are rated in micro- or picofarads.Ⅲ SMD Tantalum CapacitorsTantalum surface mount capacitors are widely used in modern electronic equipment. They provide reliable service and allow for high capacitance values to be obtained within the small package sizes required for modern equipment when designed with sufficient margins.Because of their inability to withstand the temperatures required for soldering, aluminum electrolytic types were initially unavailable in surface mount packages. As a result, for high-value capacitors in surface-mount assemblies, tantalum capacitors that could withstand the reflow soldering process were nearly the only option (SMT). Despite the availability of SMD capacitors, tantalum continues to be the capacitor of choice for SMD applications due to its excellent cost, size, and performance parameters.Surface Mount Tantalum Capacitor SizeDesignationSize (mm)EIA DesignationSize AL3.2 x W1.6 x H1.6EIA 3216-18Size BL3.5 x W2.8 x H1.9EIA 3528-21Size CL6.0 x W3.2 x H2.2EIA 6032-28Size DL7.3 x W4.3 x H2.4EIA 7343-31Size EL7.3 x W4.3 x H4.1EIA 7343-43SMD types are typically identified by three numbers. The first two are significant figures, and the third is the multiplier. The measurements are in picofarads (pF). 495E, for example, represents 4.9x105pF, which equals 4.9F. Value and unit are sometimes used to indicate values more directly.Ⅳ Applications for Tantalum CapacitorsTantalum capacitors are used in applications because of their low leakage current, high capacity, and long-term stability and reliability. They are used, for example, in the sample and hold circuits that rely on low leakage current to achieve long hold duration. Because of their small size and long-term stability, they are also commonly used for power supply filtering on computer motherboards and cell phones, most often in surface mount form. Tantalum capacitors are also available in military specifications (MIL-SPEC) versions that have tighter tolerances and a wider operating temperature range. Because they do not dry out and change capacitance over time, they are a popular replacement for aluminum electrolytic in military applications. Tantalum is also used in medical electronics due to its high stability. Tantalum capacitors are sometimes used in audio amplifiers where stability is critical.Ⅴ Construction and Properties of Tantalum CapacitorsTantalum electrolytic capacitors, like all electrolytic capacitors, have an anode, an electrolyte, and a cathode. Because the anode and cathode are separated, only a very small amount of DC leakage can pass through the capacitor. The anode is entirely made of tantalum metal. After being ground into a fine powder, the metal is sintered into a pellet at high temperatures. As a result, a porous anode with a large surface area is formed. A larger surface area translates directly into a higher capacitance value.An insulating oxide layer that acts as a dielectric is then applied to the anode. This is referred to as anodization. Because the extent of oxide growth determines dielectric thickness, this step must be precisely controlled to minimize tolerances and ensure accurate capacitance values.Pyrolysis is used to add electrolyte to the anode of solid tantalum capacitors. The solid tantalum capacitors are then immersed in a special solution before being baked in an oven to form a manganese dioxide coat. The process is repeated until all internal and external surfaces of the pellet have a thick coating. Finally, the pellet used in solid tantalum capacitors is dipped in graphite and silver to ensure a good cathode connection. In contrast to solid tantalum capacitors, wet tantalum capacitors use a liquid electrolyte. After sintered and the dielectric layer formed, the anode is immersed in a liquid electrolyte within an enclosure. The enclosure and electrolyte serve as the cathode in wet tantalum capacitors.Ⅵ Tantalum vs. Ceramic Capacitor Testing6.1 Tantalum vs. Ceramic Capacitor IR Life TestFigure 1 depicts the life test conditions for various ceramic and tantalum capacitors manufactured by various manufacturers, as well as the allowable change in insulation resistance and/or DCL/CV. Because the conditions for life testing are not standardized, direct comparisons between ceramic capacitors made by different manufacturers are difficult to make with high certainty, and direct comparisons between ceramic and tantalum capacitors are virtually impossible, except a few very high capacitance ratings.Figure 1: Life test variation between ceramic and tantalum capacitorsBecause most of the test methods used to evaluate tantalum and ceramic capacitors differ significantly, a direct comparison of their relative performance is difficult to obtain through product literature and specification data. As a result, AVX performed the following tests to provide a more direct comparison of their performance.6.2 Tantalum vs. Ceramic Comparative TestingThe AVX team chose ceramic and tantalum capacitor samples that have common ratings for both technologies and are commonly used in medical and other high-reliability applications.10μF, 16V10μF, 16V0805 case sizeX5R dielectric0805 case sizeTantalum Capacitor (TBCR106K016CRLB5000)Ceramic Capacitor (MQ05YD106KGT1AN)To ensure that special testing requirements (e.g., capacitance test frequency and DC Bias, hold times after environmental testing, etc.) could be accurately observed, collected, and compared for both basic product types, the team submitted all parts to the same test plan.Temperature Stability (MIL-PRF-55365) – 13 unitsThermal Shock (MIL-STD-202 Method 107) – 40 unitsMoisture Resistance (MIL-STD-202 Method 106) – 40 unitsThe majority of the test results showed that ceramic and tantalum capacitors performed similarly. Temperature stability, for example, revealed that ceramic capacitors are more stable in terms of equivalent series resistance (ESR) and DCL, while tantalum capacitors are more stable in terms of capacitance value over temperature. Tantalum capacitors also increased capacitance at elevated temperatures, whereas ceramic capacitors decreased capacitance at the same temperature. Furthermore, both moisture resistance and thermal shock testing resulted in stable performance for both technologies.A comparison of tantalum and ceramic capacitor parametersⅦ Why Use Tantalum Capacitors in Your PCB Design?The tantalum capacitor has extremely high stability. The tantalum capacitor will maintain the expected capacitance better over a wide temperature and frequency range. With this stability, you get more of your PCB design's expected behavior, which is especially important for filters; if the capacitance varies too much, you may lose the frequencies you want. Aside from the electrical differences, the tantalum capacitor's construction makes it highly resistant to vibration issues, improving overall system reliability.The preceding characteristics demonstrate how tantalum capacitors are uniquely suited to assist in modern electronics, but they are not without their quirks, and there are a couple of major ones to consider when designing these in. Tantalum capacitors are generally polarized devices, which means that their orientation must be carefully considered during PCB layout and assembly. This requires a little more work than a standard ceramic capacitor, but this is a characteristic of electrolyte base capacitors. When installing tantalum capacitors on a board, keep an eye out for their failure modes.