Power switch with source-bias mode for on-chip powerdomain supply drooping

摘要

This invention is an electronic circuit with a low power retention mode. A single integrated circuit includes a circuit module and a droop switch circuit supplied by a voltage regulator. In a normal mode a PMOS source-drain channel connects the voltage regulator power to the circuit module power input or isolates them dependent upon a power switch input. In a low power mode a second PMOS connected between the first PMOS gate and output diode connects the first PMOS. This supplied the circuit module from the voltage regulator power as reduced in voltage by a diode forward bias drop. This lower voltage should be sufficient for flip-flops in the circuit module to retain their state while not guaranteeing logic operation. There may be a plurality of chain connected droop switch each powering a corresponding circuit module.