Patent ID: 9705307
Date: 2017-07-11
CPC Classifications: H01L,H02H

Claim:
1. An integrated circuit, comprising: an I/O terminal for receiving a signal from a remote integrated circuit; an electrostatic discharge diode; an input/output (I/O) buffer including a buffer supply voltage node coupled through the electrostatic discharge diode to the I/O terminal; a reverse current protection (RCP) switch coupled between a power supply rail and the buffer power supply node; a voltage reference circuit configured to generate a reference voltage from a power supply voltage supplied by the power supply rail; and a control circuit powered by a buffer supply voltage carried on the buffer power supply node, wherein the control circuit is configured to open the RCP switch in response to a determination that the reference voltage is greater than the power supply voltage and to close the RCP switch in response to a determination that the reference voltage is less than the power supply voltage.