Performance Curves
Brick Dual
48Vin 3.3/1.8Vout 40W
1.8Vout
3.3Vout
1.8Vout
3.3Vout
Quarter
Figure 19:
Turn-on transient at full rated load current (resistive load)
(5 ms/div). Ch 1: 1.8Vout (1V/div); Ch 2: 3.3Vout (1V/div)
Ch 3: ON/OFF input (5V/div)
Figure 20:
Turn-on transient at zero load current (5 ms/div).
Ch 1: 1.8Vout (1V/div); Ch 2: 3.3Vout (1V/div)
Ch 3: ON/OFF input (5V/div)
1.8Vout
1.8Vout
1.8Iout
1.8Iout
3.3Vout
3.3Vout
3.3Iout
3.3Iout
Figure 21:
Output voltage response to step-change in Iout1 (50%-75%-50% of Imax;
dI/dt = 0.1A/µs). Load cap: 15µF, 300 m
Ω
ESR tantalum cap & 1µF ceramic cap.
Vout (100mV/div), Iout (10A/div). Ch1: Vout1; Ch2 Iout1; Ch 3: Vout2; Ch 4 Iout2
Figure 22:
Output voltage response to step-change in Iout2 (50%-75%-50% of Imax;
dI/dt = 0.1A/µs). Load cap: 15µF, 300 m
Ω
ESR tantalum cap & 1µF ceramic cap..
Vout (100mV/div), Iout (10A/div). Ch1: Vout1; Ch2 Iout2; Ch 3: Vout2; Ch 4 Iout2
Figure 25
source
impedance
10
µ
H
Figure 24
Figure 26
V
OUT2+
i
S
V
SOURCE
i
C
DC/DC
Converter
1
µ
F
V
OUT1+
15 µF,
300mΩ ESR
tantalum
capacitors
100 µF,
<1Ω ESR
electrolytic
capacitor
ceramic
capacitors
COM
(-)
Figure 23:
Test set-up diagram showing measurement points for Input
Terminal Ripple Current (Figure 24), Input Reflected Ripple Current
(Figure 25) and Output Voltage Ripple (Figure 26).
Product # DQ63318QMA04
Phone 1-888-567-9596
Figure 24:
Input Terminal Ripple Current, 1.8V & 3.3V outputs at 50%
rated output current and nominal input voltage with 10
µ
H source
impedance and 100
µ
F electrolytic capacitor (200 mA/div). (see Fig. 23)
Doc.# 005-2DQ638H Rev. A
1/10/03
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