Patent ID: 8773096

Claim:
A voltage regulator, comprising: an amplifier configured to generate a difference voltage responsive to a comparison of a reference voltage and a feedback voltage; an output driver operably coupled to the amplifier and configured to drive a regulated output voltage responsive to the difference voltage; an impedance circuit operably coupled between the output driver and a low power source and configured to establish the feedback voltage responsive to a current through the impedance circuit; and a variation detector operably coupled between the regulated output voltage and the difference voltage and configured to modify the difference voltage responsive to a rapid change of the regulated output voltage capacitively coupled to the variation detector, wherein the variation detector comprises: a high-side variation detector, comprising: a high-side capacitance operably coupled between the regulated output voltage and a high-side sense signal; a high-side resistance operably coupled between a high power source and the high-side sense signal; and a p-channel transistor with a source operably coupled to the high power source, a drain operably coupled to the difference voltage, and a gate operably coupled to the high-side sense signal; and a low-side variation detector, comprising: a low-side capacitance operably coupled between the regulated output voltage and a low-side sense signal; a low-side resistance operably coupled between the low power source and the low-side sense signal; and an n-channel transistor with a source operably coupled to the low power source, a drain operably coupled to the difference voltage, and a gate operably coupled to the low-side sense signal.