Electrical performance

AN2448

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The effect of the cable drop compensation is also worthy of note. Table 4 shows the output

voltage at various load amounts measured at the output connector, after the output cable.

the output voltage is nearly constant while, without this feature, at maximum load the output

voltage goes down to 4.96 V (about -3.1%). The effect of this feature is also clearly visible in

the output characteristic (Figure 12), with a flat line while in the constant voltage regulation

region.

3.3

Hold-up time

During power down phase the output voltage undergoes a clean transition without restart

trials or glitches. By observing the waveforms it is possible to measure the hold-up time. In

Figure 13.

Table 4.

Output voltage at output connector

Iout [A]

0

0.1

0.2

0.3

0.4

0.5

0.6

Vout [V] with CDC

5.12

5.13

5.13

5.14

5.14

5.15

5.15

Vout [V] without CDC

5.12

5.09

5.07

5.04

5.01

4.98

4.96

CH1: output

voltage (yellow)

CH3: rectified

input voltage

(purple)