Patent ID: 8729950
Filing Date: 2014-05-20
Classification: H02H,H03K

Abstract:
1. A voltage clamp circuit comprising: an input terminal configured to receive an input voltage; an output terminal configured to output an output voltage; a ground voltage terminal; a first controllable switch connected between the input terminal and the output terminal, the first controllable switch configured to output a first voltage to the output terminal for a first range of input voltages at the input terminal; a second controllable switch connected between the input terminal and the output terminal, the second controllable switch configured to output a second voltage to the output terminal for a second range of input voltages at the input terminal; a first zener diode connected between the output terminal and the ground voltage terminal, the first zener diode having a reverse breakdown voltage, wherein when a voltage across the first zener diode exceeds the reverse breakdown voltage, the first zener diode is configured to conduct current and maintain the output voltage at a substantially constant voltage that is less than the input voltage, wherein the second range of input voltages is greater than the first range of input voltages, wherein the first output voltage equals the input voltage for at least a portion of the first range of input voltages, and wherein the second output voltage is less than the input voltage for at least a portion of the second range of input voltages.