Step-down PWM switching power supply controller AP1510

The step-down PWM controller AP1510 chip contains circuits such as a reference voltage source, an oscillation circuit, an error amplifier, and an internal PMOS switch. It only needs a few external components such as inductors, capacitors, and diodes to form a small-sized, high-efficiency step-down controller. Voltage type switching regulated power supply.

The schematic block diagram of AP1510 is shown in Figure l1.

1. Pin functions and descriptions

1. Pin 1 (FB) feedback terminal, the inverting input of the error amplifier, is connected to the power output terminal through a voltage dividing resistor.

1. Pin 2 (EN) enable terminal, working or standby control, high level: normal operation, low level: standby operation.

1. Pin 3 (OCSET) is the output current setting terminal, and the maximum output current is set through an external resistor.

1. Pin 4 (VCC IC) is the positive power input terminal.

1. Pins 5 and 6 (Output) are the switch output terminals and the drain of the P-channel MOS field effect transistor, connected to the external freewheeling diode and inductor.

1. Pins 7 and 8 (VSS IC) power input negative terminal.

APl510 typical application circuit: