Easy Power (110-260) VAC – 12 VDC / 2A SMPS with Line Filter

The buck converter works well, with good isolation between the primary and secondary sides. The PCB design is solid, but adding a cut-out between the transformer would be better to prevent moisture from creeping into that space.

The power supply runs without noise 2 Amps and can handle 3 Amps without issues. It also shuts down in over-current situations. The components are properly rated. The DC link capacitor is a 22uF 450V, which is well above the 353V peak – this is great not to see cheap 400V caps there.

The output filter capacitors are 35V 680uF, but I suggest using 16V 1000uF capacitors instead for better filtering.

The electrolytic capacitors are from “HYNCDZ”, a Taiwanese brand that makes reliable, certified capacitors. The AC X2 metallized film capacitor is from “TENTA”, a company known for making good film capacitors.

There’s a common mode choke on the input to filter any common mode noise, which is good to see.

There’s also a class Y capacitor for reducing any common mode noise from secondary caused by primary side switching.

There are two minor issues:

1. I didn’t see any varistor or TVS diodes for surge protection. Adding them would be a plus.
2. I’d also recommend a TVS diode like P6KE15A on the output to limit surges.

A MAJOR FLAW is that at 2.17 Amps, the drum-core filter inductor on the DC output side overheats, reaching over 150°C and giving off a burning smell. I haven’t measured the DCR or inductance of the inductor yet. Even though the power supply is rated for 2A, I’d suggest using a low-value inductor – between 2.2uH and 4.7uH – rated for 3 Amps or more saturation current, with a low DCR (no more than 0.05 ohms) to handle 3A easily, keeping heat dissipation under 0.5W and voltage drop at 0.15V at 3A.

👍 nice

Is being used constantly for the past 3 weeks.
Output voltage is stable. Load around 0.4 A.
Placed order for 2 more.

Timely delivery