At 115V, this adapter’s efficiency stands at 64% under a 250mA load. It improves to 72% at 500mA, which is barely sustainable. Warmed up, crossing that 500mA threshold sees the output voltage collapse to 4V. Under 230V line input, efficiency at 250mA is slightly worse (63%), improving to 66% at 500mA and peaking at 84% under a 750mA load. There, the oscillator eventually shuts down after warming up for several minutes. All of these efficiency measurements are fair enough for level-V, which only requires 58% from 5W adapters, but they fall short of meeting VI’s 77% minimum.
Had these adapters delivered their claimed 1A output current, efficiency may have landed between decent and surprisingly good.
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