Patent ID: 6566846
Filing Date: 2003-05-20
Classification: H02M

Abstract:
A cascode circuit for generating a regulated voltage from a supply voltage, comprising:at least first and second regulator circuits being coupled in a cascode configuration for generating a regulated voltage, each regulator circuit including; a driver for generating a drive signal; a charge pump having a first voltage input coupled to a first voltage source, being responsive to the drive signal, to provide a pump voltage that is boosted from a voltage level of the first voltage source; a voltage buffer coupled between a supply voltage source and the charge pump for generating an output voltage corresponding to the pump voltage; an amplifier having a reference input coupled to a reference voltage, a sense input coupled to a sense signal representative of the pump voltage, and an output, operable in response to a difference between the reference voltage and the sense signal, to control the driver; and a switch being coupled from the amplifier output to an output of the charge pump such that the pump voltage is controllably boosted by the amplifier output through the switch.