Clamping voltage: when the transient overvoltage generating circuit, TVS avalanche principle, the current absorbed is converted into a voltage, so that the voltage is limited to a low level.
Reverse turn-off voltage: When the voltage is below this value, no change of the tube, only a very small leakage current, microamps, when the voltage is above this value, leakage current increases, the voltage continues to increase, then it will into avalanche state.
