POWER SUPPLY CIRCUIT

摘要

A power supply circuit includes a low drop out regulator generating an output voltage according to an input voltage and a booster circuit that increases responsiveness of the regulator with respect to variations in the output voltage. The regulator includes an amplifier and a first transistor that outputs the output voltage with a voltage level according to output from the amplifier. The booster circuit includes a second transistor outputting current which is proportional to output current of the first transistor and a first differential amplifier outputting a voltage signal according to a difference between a voltage corresponding to an output current of the second transistor and a reference voltage. A control circuit controls responsiveness of the amplifier according to the voltage signal.

主权项

1. A power supply circuit, comprising:
a low drop out (LDO) regulator configured to generate an output voltage according to an input voltage, the LDO regulator including:
an amplifier configured to output a voltage according to variation in the output voltage; anda first transistor that outputs the output voltage at a voltage level according to the first voltage; and a booster circuit including:
a second transistor configured to output an output current that is proportional to an output current of the first transistor;a first differential amplifier configured to output a first voltage signal according to a voltage difference between a first reference voltage and a voltage corresponding to the output current of the second transistor; anda control circuit configured to control responsiveness of the amplifier according to the first voltage signal.