TVS diode in the circuit board and the protected lines in parallel, when the instantaneous voltage than the normal operating voltage of the circuit, the TVS diode will be an avalanche, provided to the instantaneous current of an ultra low resistance path. The result is instantaneous current through the diode is divert, avoid the protected device, before and the voltage returns to normal values enable the protected circuit has a hold off voltage. When the instantaneous pulse is over, the TVS diode will automatically return to the high resistance state, and the whole circuit will enter the normal voltage.
Transient suppression diode referred to as TVS (Voltage Suppressor Transient), also called the clamp diode, by the P-N junction area, can be divided into one-way TVS and two-way TVS tube, one-way have positive and negative poles, two-way no positive and negative.
TVS diodes are widely used in semiconductor and sensitive parts of the protection, two power and signal circuit protection, as well as anti static and so on.

TVS tube is a kind of high efficiency protection device. When the poles of the TVS diode is reverse transient high impact energy, it can with 10-12 second order of magnitude speed, variable between the two poles of high impedance to low impedance, the absorption of up to a few kilowatts of power surge, between the two electrodes voltage clamp in a predetermined value, effectively protecting electronic circuit precision components from damage from various surge pulse. Coupling protection, PDAs,,, and low fast because of its response time, dynamic power, leakage current and breakdown voltage deviation is small, the clamp voltage is easy to control, no damage to the limit, small size, etc., the current has been widely used in computer systems, communications equipment, AC / DC power supply, automotive, electronic ballast, household appliances, instruments and meters RS232/422/423/485 I / O LAN ISDN, ADSL, USB, MP3, GPS, CDMA, GSM, digital camera, common mode and differential mode protection, RF / IC driver receives the protection, electromagnetic wave interference suppression, audio / video input, sensor / transmission and control circuit, relay, contactor noise suppression and other fields.
TVS that transient suppression diode, and we are more familiar with the regulator tube works, but the response is faster for the nanosecond, but the impact of surge voltage capability than the voltage regulator tube. Therefore, can be used to carry out emergency repair replacement zener diode.