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AN1537 APPLICATION NOTE

80W AC-DC adapter with PFC: evaluation results

The following diagrams compare the performance of the original design ("standard standby") with that of the

modified one ("improved standby").

To be noted in figure 14, the no-load consumption is slightly less than 0.5W @ 264Vac, then the modified 80W

adapter now meets the ECC limits, Phase 3 for the 15-50W bracket (< 0.5W @230Vac).

Figure 14. 80W AC-DC adapter with PFC: light load input consumption comparison

50

100

150

200

250

300

0,8

0,9

1

1,1

1,2

1,3

1,4

1,5

Vin [Vac]

Pin [W]

Pout = 0.5 W

Tamb= 25 °C

standard standby

improved standby

50

100

150

200

250

300

0,4

0,6

0,8

1

1,2

1,4

Vin [Vac]

Pin [W]

Pout = 0.3 W

Tamb= 25 °C

standard standby

improved standby

50

100

150

200

250

300

0,2

0,4

0,6

0,8

1

Vin [Vac]

Pin [W]

Pout = 0 W

Tamb= 25 °C

standard standby

improved standby

50

100

150

200

250

300

2

4

6

8

10

12

14

16

18

Vin [Vac]

fsw [kHz]

Tamb= 25 °C

Pout = 0.5W

Pout = 0.3W

Pout = 0W

0.001

0.01

0.1

1

3

5

10

20

30

50

100

Iout [A]

fsw [kHz]

Tamb = 25 °C

Vin = 230 Vac

Vin = 110 Vac

5