Low leakage low dropout regulator with high bandwidth and power supply rejection

摘要

A low dropout regulator produces output at an intermediate node. A resistive divider is coupled between the intermediate node and ground and provides a feedback signal to the low dropout regulator. A transistor has a first conduction terminal coupled to the intermediate node and a second conduction terminal coupled to an output node. A first impedance is coupled to the output node, a first switch selectively couples the first impedance to a supply node, a second impedance coupled to the output node, and a second switch selectively couples the second impedance to a ground node. Control circuitry is coupled to the control terminal of the transistor and to control terminals of the first and second switches. The control circuitry switches the electronic device to a power down mode by turning off transistor, closing the first and second switches, and turning off the low dropout regulator.