Patent ID: 7751157

Claim:
An over-voltage protection circuit for a linear voltage regulator comprising: a pass transistor operably coupled to receive an input voltage and regulate an output voltage to substantially a desired value, the pass transistor having a first current carrying electrode coupled to receive the input voltage, a second current carrying electrode coupled to provide a first voltage that is used to form the output voltage, and a control electrode; a plurality of diodes coupled in series between the second current carrying electrode of the pass transistor and an output of the over-voltage protection circuit; a first transistor coupled in parallel with the plurality of diodes, the first transistor having a first current carrying electrode coupled to the second current carrying electrode of the pass transistor, a second current carrying electrode coupled to the output of the over-voltage protection circuit, and a control electrode; and a third transistor having a control electrode coupled to receive a sense signal that is representative of a voltage at the second current carrying electrode of the pass transistor and a first current carrying electrode coupled to provide a control signal that causes the first transistor to be disabled responsively to the first voltage increasing to a first value that is greater than the desired value and to cause the first transistor to be enabled responsively to the first voltage decreasing to less than the first value.