Varistor is a special resistance device whose resistance value changes significantly with the change of current or voltage. Therefore, varistors are often used in circuits for the suppression of fast electromagnetic interference, and for the protection of overvoltage and overcurrent in circuits. In some applications, the role of varistor series is also widely used.
The role of varistors in series is to expand the operating voltage range of the circuit and enhance the stability of the circuit. Normally, varistors are connected in series in the circuit. Compared with the single use of varistors, series multiple varistors can achieve a higher voltage range, and can greatly improve the anti-interference ability and reliability of the circuit. Next, we will explore the role of varistors in series in detail.
First, expand the circuit operating voltage range
In many cases, the operating voltage range of the circuit is limited. Once it enters the voltage range outside the working circuit, it is easy to cause circuit damage. The series of varistors can effectively expand the voltage range of the circuit, so that the circuit can work normally in a larger voltage range. Specifically, when the varistors used in the circuit are connected in series, the voltages of each varistor share the input voltage of the circuit to achieve the effect of expanding the voltage range of the circuit.
Two, enhance the stability of the circuit
In many cases, there will be certain fluctuations in the input voltage, which will cause abnormalities in the circuit. When the varistors are used in series in the circuit, they can effectively stabilize the input current and voltage of the circuit. Specifically, when the input voltage fluctuates, the varistors of different resistance values in the circuit will change to different degrees, so as to ensure that the total current and total voltage remain stable under the condition of change.
Three, improve the anti-interference ability of the circuit
In most cases, the circuit is easily disturbed by the surrounding environment. Especially in some high-frequency applications, such as wireless communication, any external interference may lead to circuit failure. When the varistors are used in series in the circuit, they can effectively inhibit external interference and ensure the normal operation of the circuit. Specifically, when there is interference in the circuit, the varistor has a higher resistance value, which effectively reduces the input voltage and current changes caused by external interference, and ensures the reliability and stability of the circuit.
In short, through the above three ways, the varistor series can achieve good results, thereby improving the reliability and stability of the circuit, and has been widely used in many applications.