Innovation for Every Engineer.

What is A Resonator? Working Principle, Types, Comparison with Oscillator

This article is an introduction article on the resonator, information like its working principle, types, and some main parameters will be introduced in detail, also including the analysis of the difference between resonator and oscillator.




I. What is A Resonator?

II. The Working Principle of Resonator

     2.1 The Structure of Resonator

     2.2 Piezoelectric Effect

III. Resonator Types

IV. Main Parameters of Resonator

V. What’s the Difference Between Resonator and Oscillator?

5.1 General Difference Between Resonator &   Oscillator

5.2 Pros and Cons Analysis of Resonator &   Oscillator



I. What is A Resonator?

This video introduce resonator in details.


A resonator refers to an electronic component that generates a resonant frequency.


A resonator refers to an electronic component that generates a resonant frequency. It is a typical passive device and requires a peripheral circuit to drive its work to generate a clock output.


Crystal resonators are commonly divided into quartz crystal resonators and ceramic resonators. The function of generating frequency has the characteristics of stability and good anti-interference performance and is widely used in various electronic products.


The frequency accuracy of quartz crystal resonators is higher than that of ceramic resonators, but the cost is also higher than that of ceramic resonators. The resonator mainly plays the role of frequency control, and all electronic products involve frequency transmission and reception require a resonator. The types of resonators can be divided into the in-line type and patch type according to their appearance.

II. The Working Principle of Resonator


2.1 The Structure of Resonator


Quartz crystal resonator is a kind of resonant device made by using the piezoelectric effect of quartz crystal (a crystal of silicon dioxide).


Its basic composition can be roughly described as follows: cut a thin slice (referred to as a wafer, which can be square, rectangular or circular, etc.) from a piece of quartz crystal at a certain azimuth angle, and coat silver layers as electrodes on its two corresponding surfaces. Weld a lead wire on each electrode to the pin, and add a package shell to form a quartz crystal resonator. Its products are generally packaged in metal shells, but also in glass, ceramic or plastic packages.


2.2 Piezoelectric Effect


If an electric field is applied to the two electrodes of the quartz crystal, the wafer will be mechanically deformed. Conversely, if mechanical pressure is applied to both sides of the wafer, an electric field will be generated in the corresponding direction of the wafer. This physical phenomenon is called the piezoelectric effect.


If an alternating voltage is applied to the two poles of the wafer, the wafer will produce mechanical vibration, and at the same time, the mechanical vibration of the wafer will produce an alternating electric field. In general, the amplitude of the mechanical vibration of the wafer and the amplitude of the alternating electric field is very small, but when the frequency of the applied alternating voltage is a certain value, the amplitude is obviously increased, which is much larger than the amplitude at other frequencies. This phenomenon is called piezoelectric resonance, which is very similar to the resonance phenomenon of the LC circuit. Its resonant frequency is related to the cutting method, geometry, and size of the wafer.

III. Resonator Types


Quartz crystal resonators are composed of quartz crystal resonators (ie resonators and oscillation circuits) with extremely high-quality factors. The quality of the crystal, the cutting orientation, the structure of the crystal oscillator and the circuit form, etc., jointly determine the performance of the resonator.


The International Electrotechnical Commission (IEC) divides quartz crystal resonators into 4 categories: ordinary crystal oscillator (SPXO), voltage-controlled crystal resonator (VCXO), temperature compensated crystal oscillator (TCXO), and thermostatically controlled crystal oscillator (OCXO). Digitally compensated crystal loss oscillation (DCXO) is currently under development.


(1) Ordinary crystal resonator (SPXO) can produce frequency accuracy of the order of 10-5~10-4, the standard frequency is 100MHZ, and the frequency stability is ±100ppm. SPXO does not use any temperature and frequency compensation measures are low in price and are usually used as a clock device for microprocessors. The package size ranges from 21×14×6mm and 5×3.2×1.5mm.


(2) The accuracy of the voltage-controlled crystal resonator (VCXO) is in the order of 10-6 to 10-5, and the frequency range is 1 to 30 MHz. The frequency stability of the low-tolerance resonator is ±50ppm. Usually used in phase-locked loops. The package size is 14×10×3mm.


(3) The temperature-compensated crystal resonator (TCXO) uses temperature-sensitive devices for temperature and frequency compensation, with a frequency accuracy of 10-7~10-6, a frequency range of 1-60MHz, and frequency stability of ±1~±2.5ppm, The package size ranges from 30×30×15mm to 11.4×9.6×3.9mm. Usually used in handheld phones, cellular phones, two-way wireless communication devices, etc.


(4) The thermostatically controlled crystal resonator (OCXO) places the crystal and oscillation circuit in a thermostat to eliminate the influence of environmental temperature changes on the frequency. The frequency accuracy of OCXO is in the order of 10-7~10-8, even higher for some special applications. The frequency stability is the highest among the four types of resonators.

IV. Main Parameters of Resonator


The main parameters of the crystal oscillator are nominal frequency, load capacitance, frequency accuracy, frequency stability, etc. Different crystal oscillators have different nominal frequencies, and most of the nominal frequencies are marked on the crystal housing.


For example, the nominal frequencies of common ordinary crystal oscillators are 48kHz, 500 kHz, 503.5 kHz, 1MHz~40.50 MHz, etc. The frequency of crystal oscillators with special requirements can reach 1000 MHz or more, and there are also non-nominal frequencies, such as CRB, ZTB, Ja, etc.


The load capacitance refers to the sum of all the effective capacitances inside and outside the IC block connected by the two leads of the crystal oscillator, which can be regarded as the series connection capacitance of the crystal oscillator in the circuit. The different load frequency determines the different oscillation frequency of the resonator. For crystal oscillators with the same nominal frequency, the load capacitance may not be the same.


Because the quartz crystal resonator has two resonant frequencies, one is a low-load capacitance crystal of a series resonant crystal oscillator, and the other is a high-load capacitance crystal of a parallel resonant crystal. Therefore, when the crystal oscillators with the same nominal frequency are exchanged, the load capacitance must be the same, and they cannot be exchanged rashly, otherwise, it will cause the electrical appliances to work abnormally.


Frequency accuracy and frequency stability: Because the basic performance of ordinary crystal oscillators meets the requirements of general electrical appliances, certain frequency accuracy, and frequency stability are required for high-end equipment. Frequency accuracy varies from magnitude to magnitude. The stability varies from ±1 to ±100ppm. Choosing the appropriate crystal oscillator according to the specific equipment needs, such as communication network, wireless data transmission and other systems require a more demanding quartz crystal resonator.


Therefore, the parameters of the crystal oscillator determine the quality and performance of the crystal oscillator. In practical applications, the appropriate crystal oscillator should be selected according to specific requirements. Because of the different prices of crystal oscillators with different performances, the higher the requirements, the more expensive the price. Generally, the choice only needs to meet the requirements.

V. What’s the Difference Between Resonator and Oscillator?



5.1 General Difference Between Resonator & Oscillator


The so-called resonator includes not only quartz crystal resonators but also ceramic resonators, LC resonators, and so on. A crystal oscillator is the abbreviation of the crystal oscillator. It is an oscillator component composed of a combination of a crystal resonator and a circuit, especially an oscillator component made of a quartz crystal.


So the complete naming should be "Quartz Crystal Resonator" and "Quartz Crystal Oscillator". In addition, the resonator is a passive device, which requires a peripheral circuit to drive its work and generate a clock output. The oscillator is an active device with its own built-in circuit to provide a more stable clock output.


A crystal oscillator is an oscillating circuit that uses a crystal as a frequency-selecting component. Compared with other oscillating circuits, it has the advantages of good frequency selection characteristics (high Q value) and high-frequency stability.


The fundamental difference between a resonator and an oscillator is active and passive, which can also be said to be active and passive. The oscillator has one more control circuit than the resonator.


Crystal resonators have some equivalent parameters, and different use environments may have different requirements. For example, some users require load capacitance C0 / C1. When selecting, consider the environmental temperature, load capacitance, frequency accuracy, and even DLD requirements. This requires some control of the parameters of the peripheral oscillator circuit to output a stable frequency.


The crystal oscillator avoids these troubles. The oscillating circuit has been completed by the manufacturer, and only a stable power supply is needed to have a stable output. In addition, the oscillator has some auxiliary functions, such as voltage-controlled crystal oscillator (VCXO), temperature-compensated crystal oscillator (TCXO), constant temperature crystal oscillator (OCXO), etc. These oscillators can meet some precision controls that are difficult to achieve when directly using resonators. . The frequency accuracy of OCXO can reach the order of E-9.


Secondly, the crystal oscillator is made of a crystal resonator, in order to be used as a signal carrier or timing on other components. To meet the requirements of the products produced.


An oscillator is simply a frequency source and is generally used in a phase-locked loop. In detail, it is a device that can convert DC power into AC power without external signal excitation. Generally divided into two types: positive feedback and negative resistance.


The so-called "oscillation", its meaning implies exchange, the oscillator includes a process and function from no oscillation to oscillation. It can complete the conversion from DC power to AC power. Such a device can be called an "oscillator."


Any communication or electronic system should have a level value within a normal range at some given point. The components that are adjusted to the normal level value are amplifiers and attenuators. The point of excessively low level is the point where noise is introduced, and the point of excessively high level will cause overload and make the amplifying component appear intolerable nonlinear distortion. It is not difficult to understand the role of the attenuator. There are two types of attenuators: fixed and variable.



5.2 Pros and Cons Analysis of Resonator & Oscillator


In this sector, we are going to analyze the pros and cons of crystal resonator and ceramic resonator, resonator, and oscillator.


(1) pros and cons of crystal resonator and ceramic resonator


The introduction of the crystal resonator has been mentioned above, so I won't repeat it here. Let's take a look at ceramic resonators.


A ceramic resonator is a piezoelectric ceramic device used to oscillate at a specific frequency. The materials used to make such devices excite resonance characteristics during the production process.


Because this resonance characteristic is within the production error range, and its quality factor is much lower than that of quartz, the frequency stability that ceramic resonators can provide is not as good as crystal resonators. Generally, ceramic resonators are used in occasions where the cost is low and the performance requirements are not high.


Pros: Compared with crystals, the cost of ceramic resonators is only half that of crystals and the size is smaller.


Cons: Compared with crystals, it lacks frequency and temperature stability. Its accuracy is poor, probably between 1% and 0.1%.



(2) pros and cons of resonator and oscillator


The oscillator is an energy conversion device that converts DC power into AC power with a certain frequency. The circuit formed by it is called an oscillator circuit. The oscillator is an active device. The oscillator has one more control circuit than the resonator.


Oscillators are electronic components used to generate repetitive electronic signals (usually sine waves or square waves). The circuit formed by it is called an oscillating circuit. An electronic circuit or device that can convert direct current into an alternating current signal with a certain frequency.


There are many types. According to the oscillation excitation mode, it can be divided into the self-excited oscillator and separately excited oscillator; according to the circuit structure, it can be divided into the resistance-capacitance oscillator, inductance-capacitance oscillator, crystal oscillator, tuning fork oscillator, etc.; according to the output waveform can be divided into It is a sine wave, square wave, sawtooth wave, and other oscillators. It is widely used in the electronics industry, medical treatment, scientific research, etc.


Pros: The crystal oscillator signal quality is good, relatively stable, and the connection method is relatively simple (mainly to do a good job of power filtering, usually a PI filter network composed of a capacitor and an inductance is used, and the output terminal uses a small resistance resistor to filter the signal. Yes), no complicated configuration circuit is required. For applications with sensitive timing requirements, the performance of crystal oscillators is relatively good.


Cons: Compared with the crystal resonator, the defect of the crystal oscillator is that its signal level is fixed, and the appropriate output level needs to be selected. It is less flexible and expensive. In addition, the quartz oscillator takes a long time to start.


Volume: Compared with passive crystals, crystal oscillators are usually larger in volume. With the improvement of technology, some crystal oscillators are now surface-mounted, and the volume is comparable to crystal resonators.


Summary: The typical initial accuracy of ceramic resonators is in the range of 0.5% to 0.1%, and drift caused by aging or temperature changes may change this accuracy range.


The tolerances of cheap ceramic resonators are only ±1.1%, and the accuracy of higher-end automobiles is ±0.25% and ±0.3%, respectively. The future application lies in the automotive CAN (controller area network) bus application with an operating temperature of -40°C to +125°C. Low-cost ceramic resonators with frequencies ranging from 200 kHz to about 1 GHz are suitable for embedded systems that do not have strict timing requirements.


Ceramic devices start faster and are generally smaller than quartz devices. They are also more able to withstand shock and vibration.





1. What does a resonator do?

A resonators' sole purpose in life is to change a vehicle's engine noise before it reaches the muffler for a final decibel reduction.


2. What is a resonator in electronics?

A resonator is a device or system that exhibits resonance or resonant behavior. ... Resonators are used to either generate waves of specific frequencies or to select specific frequencies from a signal. Musical instruments use acoustic resonators that produce sound waves of specific tones.


3. What does removing the resonator do?

A resonator delete changes the way that the pulses generated by your vehicle move through the exhaust system. Think of this device as if it were a large echo chamber. It takes those pulses, optimizes their frequencies, and this makes it possible to achieve better power production.


4. Which is better muffler delete or resonator delete?

If you want a louder and lighter vehicle, you'll be better off with the muffler delete. If you're after a good sound and a little more power, the resonator delete is the way to go. ... After all, the difference between a resonator delete and muffler delete isn't that significant.


5. What is difference between crystal and resonator?

The ceramic resonator utilizes a frequency within the electrical component but unlike the crystal which has a frequency tolerance of 10~30 PPM , a ceramic resonator carries a 0.5% or 5,000 PPM frequency tolerance which is generally used in microprocessor applications where absolute stability is not important.


6. Is intake resonator necessary?

An air intake resonator is a crucial component to an automobile engine's intake system. It allows the engine to run more quietly as well as more efficiently. ... An air intake resonator is a crucial component to an automobile engine's intake system. It allows the engine to run more quietly as well as more efficiently.


7. Do resonators restrict airflow?

Magnaflow resonators dont restrict flow at all, its just like adding a section of straight pipe as they are straight through. magnaflow's design uses no chambers, but rather a perforated straight pipe surrounded by a sound-absorbing material.


8. Which is the best frequency for a noise resonator?

The resonator is designed to work best in the frequency range where the engine makes the most noise; but even if the frequency is not exactly what the resonator was tuned for, it will still produce some destructive interference.


9. Will a resonator quiet my exhaust?

Mufflers and resonators work together to quiet your car's exhaust and reduce annoying sounds. While they function differently, they both help improve your exhaust note. Mufflers and resonators can also be deleted for a louder, more aggressive exhaust sound.


10. Does removing the resonator increase horsepower?

As a rule; the quieter an exhaust system is, the more horsepower it is stealing from your engine. ... Removal of all mufflers and resonators will provide slightly greater increases but remember as the restrictions are removed the exhaust grows louder.