"Voltage -sensitive resistance is a resistance device with non -linear ambush characteristics. It is mainly used to perform voltage clamping when the circuit is affected by overvoltage, and absorb excess current to protect sensitive devices.
Principles of pressure -sensitive resistance working principles
Voltage -sensitive resistance is a non -linear resistor with metal oxide semiconductor with zinc oxide as the main ingredient. As the voltage added on it continues to increase, its resistance value can be changed from MΩ (Zhaou) level to MΩ (millilitermia (milliligueEuropean) level.When the voltage is low, the voltage -sensitive resistance works in the leakage current area, showing a large resistance, and the leakage current is small; when the voltage enters the non -linear region, the current changes in a considerable range, and the voltage changes are not large., Present a better voltage limit characteristics; the voltage increases again, the voltage -sensitive resistance enters the saturated area, showing a small linear resistance. Due to the large current, the voltage resistance will cause overheating and even burst.When normal use, the voltage -sensitive resistance is in the leakage current area. When it is impacted by the surge, it enters the non -linear area to leak the wave current. Generally, it cannot enter the saturated area.
How to measure pressure -sensitive resistance
For the measurement of the pressure -sensitive resistance, some people say that it is possible, and some people say no. The use of pressure -sensitive resistance is generally in parallel in the circuit. When the voltage at both ends changes sharply, the voltage -sensitive resistance will be short -circuited to bring insideThe current fuse is fused, and a certain extent plays a role in protecting.The role of the pressure -sensitive resistance in the circuit is used to protect and stabilize the voltage when the power supply appears at a high voltage. When measured, the position of the universal table is located at the 10K gear, and then the tablet is connected to the two ends of the resistance.The resistance value of the pressure -sensitive resistance will be displayed. If it is far more than this value, it means that the voltage resistance is damaged.
Voltage -sensitive resistance parameter
There are many parameters of the pressure -sensitive resistance. I will introduce some of the main parameters here.1. Residual voltage: The residual voltage is the most peak voltage at both ends when the voltage resistance is relatively large when the waveform is relatively large. This voltage is called residual voltage.2. Leakage current: The leakage current means that when the voltage on the effect and the voltage resistance is the reference voltage, the current on the allergic resistance is called the leakage current.3. Portable capacity: Within the specified time interval and number, add the specified waveform current to the pressure -sensitive resistance, and the voltage resistance will change. The change in the reference voltage will still be in the specified rangeInternal circulation current, the maximum value of this circulating current is the popular capacity.
Voltage resistance selection
Although the pressure -sensitive resistance can absorb a large surge power energy, it cannot withstand the continuous current above the milliam level. This must be considered when used as an overvoltage protection.For the selection of voltage -sensitive resistance, the nominal voltage voltage voltage V1MA and the stream capacity are generally selected.
The role of pressure -sensitive resistance
The greatest advantage of pressure -sensitive resistance is that when the threshold value of the voltage resistance itself is greater than the voltage given by it, the current flow value in the circuit is very small.At the time of large, the resistance value in the circuit decreased, and the current increased, which eventually reduced the impact of voltage on the circuit.Through this role, we can protect the circuit in the voltage resistance, prevent the circuit from being affected by the voltage, so that the value of the voltage will not change too much.

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