Patent ID: 8067986

Claim:
A differential amplifier, comprising: a first device configured to be a replica of a first output driver of the differential amplifier; a second device configured to be a replica of a second output driver of the differential amplifier; a thin oxide device coupled to a gate terminal of the first output driver; a comparator configured to generate a threshold current, and to compare the threshold current to a sum of a first current through the first device and a second current through the second device; and a clamp circuit configured to limit at least one of a third current through the first output driver or a fourth current through the second output driver if the comparator determines that the sum of the first current and the second current has a predetermined relationship with the threshold current; wherein a voltage of a gate terminal of the first device is configured to increase if a decrease in a power supply voltage occurs; and wherein the clamp circuit is configured to limit the third current through the first output driver due to the increase in the voltage of the gate terminal of the first device, thereby preventing damage to the thin oxide device due to the decrease in the power supply voltage.