Power supply circuit and terminal device

The invention discloses a power supply circuit and a terminal device. The power supply circuit comprises a detection module, a boost module, a voltage reducing module and a switching circuit. The detection module is connected with the switching circuit, acquires working state information of the terminal device and outputs first control information or second control information to the switching circuit. The first end of the switching circuit is connected with the detection module, the second end of the switching circuit is connected with the output end of the boost module and the input end of the voltage reducing module, and the third end of the switching circuit is connected with the output end of the voltage reducing module and the input end of the power amplifier. The boost module is connected with the voltage reducing module, and supplies power to the power amplifier through the switching circuit when the switching circuit is switched on. The power amplifier is supplied by power through the voltage reducin