APPARATUS AND METHODS FOR AMPLIFIER FAULT PROTECTION

摘要

An amplifier includes a fault protection control circuit biased from the signal pin and a fault protection circuit including a first PMOS transistor and a second PMOS transistor. The sources and bodies of the first and second PMOS transistors can be connected to one another, the drain of the first PMOS transistor can be connected to the amplifier's output, and the drain of the second PMOS transistor can be connected to a signal pin. During normal operating conditions, the fault protection control circuit can turn on the first and second PMOS transistors. However, the fault protection control circuit can turn off the first PMOS transistor and turn on the second PMOS transistor when an overvoltage condition is detected, and can turn on the first PMOS transistor and turn off the second PMOS transistor when an undervoltage condition is detected, even when the integrated circuit is unpowered.