Patent ID: 7030680
Filing Date: 2006-04-18
Classification: G05F,H03K

Abstract:
1. An integrated circuit having an on chip power supply coupled to a field effect transistor having a source, a drain, a gate and a body, the power supply comprising: a charge storage device and a current directing device; a first terminal of the charge storage device being connected to the source of the field effect transistor, a second terminal of the charge storage device being connected to a anode of the current directing device, and an cathode of the current directing device being connected to the drain of the transistor; a control circuit coupled to be powered by a voltage between the first and second terminals of the charge storage device and to control the gate of the field effect transistor; the body of the field effect transistor being connected to the drain, the control circuit being responsive to the polarity of the voltage between the source and the drain to turn the field effect transistor on when the drain is at a positive voltage relative to the source and off when the drain is at a negative voltage relative to the source.