POWER SUPPLY CIRCUIT

摘要

A power supply circuit comprises a boost circuit, and further comprises a second capacitor (C2), a third capacitor (C3), and a second diode (D2). The second capacitor is connected between a connecting point, of a switch tube (Q1) in the boost circuit and a boost inductor (L1), and the anode of a boost diode (D1). The cathode of the boost diode passes sequentially through an output filtering capacitor (C1) in the boost circuit and a third capacitor, to be connected to a voltage reference terminal. The cathode of the second diode is connected to the anode of the boost diode. The anode of the second diode is connected to a connecting point of the third capacitor and the output filtering capacitor. The power supply circuit has a simple manufacturing process, makes it easy to achieve low costs and miniaturization, and is especially applicable in scenarios of micro power and small power switching power supplies.