Product # PQ65180QGA06

Phone 1-888-567-9596

Doc.# 005-2QG581D Rev. B

9/14/04

Page 7

Performance Curves

48Vin 18Vout 5.6A

Quarter

Quarter

Brick

Brick

Figure 14: Input Terminal Ripple Current, ic, at full rated output cur-

electrolytic capacitor (100 mA/div). See Figure 13.

inductor at nominal input voltage and rated load current (5 mA/div).

See Figure 13.

Figure 16: Output voltage ripple at nominal input voltage and rated

Figure 13: Test set-up diagram showing measurement points for Input

Terminal Ripple Current (Figure 14), Input Reflected Ripple Current

(Figure 15) and Output Voltage Ripple (Figure 16).

0

2

4

6

8

10

12

14

16

18

20

012

3456

789

40 V

48 V

75 V

Figure 17: Output voltage vs. load current showing typical current limit

curves and converter shutdown points.

Figure 18: Load current (5A/div) as a function of time when the con-

verter attempts to turn on into a 10 m

Ωshort circuit. Top trace

(2.0ms/div) is an expansion of the on-time portion of the bottom trace.

source

impedance

DC/DC

Converter

See Fig. 15

See Fig. 14

See Fig. 16

ceramic

capacitor

10 µF,

100m

Ω ESR

tantalum

capacitor

47 µF,

<1

Ω ESR

electrolytic

capacitor

i

S

i

C