Abstract: A high-voltage transient protection circuit for use in combination with a voltage regulator of the type employing an error amplifier to compare a portion of the controlled output voltage against a reference voltage and adjust the output voltage accordingly. The protection circuit can be used with three terminal positive or negative voltage regulators of either the shunt transistor or series pass transistor types. Oscillation of the protection circuit around a selected transient voltage threshold is avoided by providing a hysteresis characteristic in the response of the circuit to a voltage transient. The circuit is preferably embodied as an integrated circuit in a chip of semiconductor material and is particularly well suited for protecting a voltage regulator and associated electronic systems from the detrimental voltage transients encountered in an automotive environment.