Test setup and performance summary

AN2565

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Figure 21.

OUT2 switching frequency vs. load current

10.7

Linear regulator output voltages vs. output current

Figure 22 shows the load regulation for the internal linear regulator LDO5. Both switching

Figure 22.

LDO5 output vs. load current

10.8

Load transient response

The following figures show the load transient response from 1 A to 4 A for both switching

outputs. In each of these cases the PM6680A works in forced PWM mode (the SKIP pin is

high).

OUT2=1.8V Switching Frequency

0

50

100

150

200

250

300

0.01

0.10

1.00

10.00

Load current [A]

SKIP @ 12V

SKIP @ 24V

SKIP @ 32V

NO AUD. SKIP @ 12V

NO AUD. SKIP @ 24V

NO AUD. SKIP @ 32V

PWM @ 12V

PWM @ 24V

PWM @ 32V

LDO5 vs. OUTPUT CURRENT

4.9790

4.9800

4.9810

4.9820

4.9830

4.9840

4.9850

4.9860

4.9870

4.9880

4.9890

0

1020

3040

50

6070

8090

100

LOAD CURRENT [mA]