Inventors:
Scott D. Carper - San Jose CA, US
Assignee:
National Semiconductor Corporation - Santa Clara CA
International Classification:
G05F 1/10
Abstract:
A low-dropout regulator is provided. The low-dropout regulator includes a p-type depletion transistor as a pass device. The low-dropout regulator further includes switch circuitry and a charge pump that provides, at its output, a voltage greater than VDD. The source of the p-type depletion transistor is coupled to VDD. Under normal operating conditions, the bulk of the p-type depletion transistor is coupled to the source of the p-type depletion transistor. However, if the voltage at the gate of the p-type depletion transistor gets close to VDD, the switch circuitry causes the bulk of the p-type transistor to be coupled to the output of the charge pump instead.