AN2432

Functional check

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3.3

Power-down

Unplugging the adapter from the mains, the self supply and output voltages have clean

transition without restart trials or glitches. Figure 15 and Figure 16 show the power-down

waveforms at full load. It is possible to measure the hold-up time that, in the worst case

Figure 13.

Figure 14.

CH1: Q3 drain voltage

CH2: Output voltage

CH3: Self supply voltage

CH1: Q3 drain voltage

CH2: Output voltage

CH3: Self supply voltage

Figure 15.

Figure 16.

CH1: Q3 drain voltage

CH2: Output voltage

CH3: Self supply voltage

CH1: Q3 drain voltage

CH2: Output voltage

CH3: Self supply voltage