Patent ID: 7012456

Claim:
A circuit for discharging a high voltage signal to a supply voltage line, the circuit comprising: a first switch receiving the high voltage signal, the first switch having an output; a second switch having an input coupled with the output of the first switch, the second switch having an output; a third switch having an input coupled with the output of the second switch, the third switch having an output coupled with the supply voltage line; and a fourth switch for clamping said high voltage signal to a ground, the fourth switch having an input coupled with the high voltage signal and an output coupled with said ground; wherein when the first, second, and third switches are on, the high voltage signal discharges to the supply voltage line; and wherein the fourth switch has a control coupled with the output of the first switch such that when the high voltage signal is discharging and approaches a voltage level of approximately said ground, the fourth switch turns on and clamps the high voltage signal to said ground.