Power supply control circuit

摘要

A power supply control circuit for conditioning an electronic circuit's input voltage at ground or at the operation voltage of an external power supply so as to permit the electronic circuit to receive a supply voltage at ground potential until the power supply transitions above a threshold voltage level and thereafter to provide operation level voltage of the power supply to the electronic circuit. The circuit comprises a transconducting means having its high current node coupled to an external power supply, its controlling node coupled to a voltage reference means. The transconducting means has its controlled high current node coupled through a power input node to the power input for the electronic circuit to condition the voltage received thereby. The power input node is in turn coupled through a pull down means to ground potential.