Patent ID: 7457091

Claim:
A protection circuit for protecting a drive field effect transistor, the protection circuit comprising: a voltage control circuit comprising: a positive field effect transistor coupled to a power source; a negative field effect transistor coupled to a pass-gate and a circuit input terminal wherein a drain of the negative field effect transistor couples to a gate of the positive field effect transistor; wherein when the circuit input terminal is low, the pass-gate is on and when the circuit input terminal is high, the pass-gate is off; and a plurality of diode connected field effect transistors and a plurality of resistors in series with the plurality of diode connected field effect transistors, the pluralities forming a high resistance path to limit current from the power source; wherein the voltage control circuit is coupled to a stacked field effect transistor section by a voltage control line connecting the plurality of diode connected field effect transistors and plurality of resistors; the stacked field effect transistor driver section comprising: at least three field effect transistors wherein at least one of the at least three field effect transistors is continually on and wherein the pass-gate is configured to turn on at least one top field effect transistor to pull a terminal voltage close to ground to protect at least one bottom drive field effect transistor.