DN05061/D, Universal AC Input, 5 Volt Output, 10 Watt Power Supply Design Note

DN05061/D, Design Note describes a simple 10 watt, universal AC input, constant output voltage power supply intended for AC adapters, industrial equipment, or white goods, where isolation from the AC mains is required, and low cost, high efficiency, and low standby power are essential. The featured power supply is a simple CCM flyback topology utilizing NCP1124 monolithic with integral 9-ohm, vertical channel MOSFET in a PDIP7 package (U1). This Design Note provides the complete circuit schematic details and BOM for 5V, 2A power supply. The simple input EMI filter (C1, L1) is adequate to pass Level B for FCC conducted EMI compliance. The NCP431 programmable zener is used as an error amplifier (U3), plus an optocoupler feedback scheme (U2) provides for excellent line and load regulation with high input-to-output safety isolation