Supply voltage reference circuit

摘要

A supply reference voltage circuit is coupled to an output node, a supply voltage node and a supply reference voltage node and is operable to connect the output node to the supply reference voltage node and prevent current flow through an output device coupled to the output node in response to sensing a low voltage level at the supply voltage node and a non-zero voltage at the output node. The circuit is further operable to connect the supply reference voltage node to the supply voltage node in response to the voltage at the output node being a threshold voltage above the voltage at the supply voltage node. The circuit is further operable to bypass a blocking diode in response to sensing a high voltage level at the supply voltage node.