Patent ID: 7746153
Filing Date: 2010-06-29
Classification: H03K

Abstract:
1. A voltage regulation circuit that is arranged to recover charge at a gate of an output transistor, comprising: a first switching transistor having a drain terminal that is coupled to the gate of the output transistor and a source terminal that is coupled to a positive terminal of a boot strap capacitor, wherein the conduction of the first switching transistor enables the output transistor to also conduct and to provide a positive output voltage at a source terminal of the output transistor that is coupled to an output terminal; a second switching transistor having a drain terminal that is coupled to the gate of the output transistor and a source terminal that is coupled to the source terminal of the output transistor, wherein conduction of the second switching transistor enables the output transistor to stop conducting and which causes a voltage at or below ground to be provided at the source terminal of the output transistor; a switching device that is coupled between the gate of the output transistor and a capacitor coupled to a positive terminal of a voltage supply, wherein the switching device is arranged to start conducting as the output transistor transitions from conduction to non-conduction, and wherein the conduction of the switching device enables at least a portion of charge at the gate of the output transistor to flow to the capacitor coupled to the positive terminal of the voltage supply; and a control circuit that is separately coupled to a gate of the first switching transistor and a gate of the second switching transistor, wherein the operation of the control circuit is arranged to separately control when the first and second switching transistors separately transition between conduction and non-conduction so that the charge at the capacitor is reused at the gate terminal of the output transistor to enable its conduction.