AP3981B/C/D2 Power Switchers

Diodes Incorporated AP3981B/C/D2 Power Switchers are integrated with a primary-side regulation controller and an N-channel power MOSFET. These Diodes Incorporated power switchers can achieve accurate Constant Current (CC) and Constant Voltage (CV) without requiring an optocoupler. The AP3981B/C/D2 power switchers operate in peak current Amplitude Modulation (AM) mode and Pulse Frequency Modulation (PFM) mode. This forms a fine-tuned frequency curve within the whole power range, allowing the power switchers to achieve high average efficiency and improve audible noise. These power switchers are capable of providing comprehensive protection without the need for additional circuitry. The AP3981B/C/D2 power switchers offer V_CC over-voltage protection, output over-voltage protection and under-voltage protection, output short circuit protection, cycle-by-cycle current limit, open-loop protection, and internal OTP. Typical applications include routers, Set-Top Box (STB) power supplies, and network adaptors.