Circuitry to prevent overvoltage of circuit systems

Abstract

An overvoltage protection method and circuit includes a positive supply input node, an output node, and a negative supply node. The overvoltage protection circuit further includes a first functional circuit configured to turn ON a MOSFET and maintain it in a low resistance state. A second functional circuit is configured to detect an overvoltage and control the gate of the MOSFET to regulate a voltage at the output node. A third functional circuit is configured to provide a startup wherein the overvoltage protection circuit is not damaged and/or to regulate an operating voltage such that an overvoltage does not appear on the overvoltage protection circuit. The external components include the MOSFET, which has a gate coupled to the output of the charge pump of the overvoltage protection circuit.

Dependencies are inferred from the claim text.