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How to judge the quality of transient suppression diode?

How to judge the quality of transient suppression diode?

The transient diode, called TVs for short, is a kind of diode type high-efficiency protective device. When the two poles of the TVS diode are impacted by the reverse transient high energy, it can change the high impedance between the two poles into the low impedance at the speed of 10 to 12 seconds, absorb the surge power up to several kilowatts, make the voltage clamp between the two poles at a predetermined value, effectively protect the precise components in the electronic circuit from the damage of various surge pulses.

TVS features:
1. When TVS diode is added to the signal and power line, it can prevent the failure of microprocessor or microcontroller caused by instantaneous pulse, such as electrostatic discharge effect, surge of AC power supply and noise of switching power supply.
2. The electrostatic discharge effect can release more than 10000v, 60A pulse and last for 10ms, while the general TTL device will be damaged when it encounters more than 30ms 10V pulse. The TVS diode can effectively absorb the pulses that will damage the device and eliminate the crosstalk caused by switches between buses.
3. Placing the TVS diode between the signal line and the grounding can avoid unnecessary noise influence on the data and control bus.

TVS diode measurement judgment:
1. Use multimeter R & ties; 1K to measure the quality of pipes
For monopole TVs, the forward and reverse resistances can be measured according to the method of measuring ordinary diodes. Generally, the forward resistance is about 4k5, and the reverse resistance is infinite.
2. For the two-way pole type TVs tube, the resistance between the two pins measured by changing the red and black probes arbitrarily should be infinite, otherwise, the tube performance is poor or damaged.
The method of judging and measuring the polarity of bidirectional thyristor:
(1) Put the three meter at rx1, and measure its three pins, as shown in the table. No matter how the red probe measures, the resistance between T1 and G is 20 to 50 m, so the other pin is T2.
(2) Place the three electricity meters in rx1, connect the test rods to T2 and T1 of the thyristor respectively, connect T2 and G with wires and move them away, then the resistance between T2 and T1 is low (the thyristor has been triggered), and the resistance is set as R1.
(3) Then use three meters to measure T2 and g respectively. Connect T2 and T1 with wires and move them away. Then there is a low resistance between T2 and G (thyristor has been triggered). Set the resistance as R2, usually R1 is less than R2, then T1 and G can be distinguished.