The circuit symbol of the transient voltage suppressor is the same as that of the ordinary voltage regulator. Its voltage-current characteristic curve.

The forward characteristics are the same as those of ordinary diodes, and the reverse characteristics are typical of PN junction avalanche devices. Under the action of surge voltage, the transient voltage suppressor bipolar voltage rises from the rated reverse turn-off voltage VWM to the breakdown voltage VBR, and is broken down. With the emergence of the breakdown current, the current flowing through the transient voltage suppressor will reach the peak pulse current IPP, and the voltage at both ends will be clamped below the predetermined maximum clamp voltage VC. Then with the exponential attenuation of the pulse current, the voltage at the two poles of the instantaneous voltage suppressor also continues to decline, and finally returns to the initial state, which is the process of suppressing the possible surge pulse power and protecting electronic components.