Performance Curves
Brick
Eighth
48V 5.0V
10A
out
in
Figure 15
10
µH
Figure 14
source
impedance
Figure 16
iS
iC
DC/DC
Converter
VOUT
VSOURCE
10
µ
Ω
F,
ESR
1 µF
47 µF,
ceramic
100m
<1
Ω ESR
capacitor
tantalum
electrolytic
capacitor
capacitor
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).
Figure 14: Input Terminal Ripple Current, i , at full rated output cur-
c
rent and nominal input voltage with 10
µH source impedance and 47µF
electrolytic capacitor (200 mA/div). See Figure 13.
Figure 15: Input reflected ripple current, i , through a 10 µH source
Figure 16: Output voltage ripple at nominal input voltage and rated
load current (20 mV/div). Load capacitance: 1 F ceramic capacitor
and 10 F tantalum capacitor. Bandwidth: 20 MHz. See Figure 13.
s
inductor at nominal input voltage and rated load current (5 mA/div).
See Figure 13.
µ
µ
6.0
5.0
4.0
35 V
3.0
48 V
75 V
2.0
8
9
10
11
12
13
14
Load Current (A)
Figure 17: Output voltage vs. load current showing typical current limit
Figure 18: Load current (5A/div) as a function of time when the con-
verter attempts to turn on into a 10 m short circuit. Top trace
(2.5ms/div) is an expansion of the on-time portion of the bottom trace.
curves and converter shutdown points.
Ω
Product # PQ60050EML10
Phone 1-888-567-9596
Doc.# 005-2EM650E Rev. A 5/22/03 Page 7