
0
10
20
30
40
50
60
025
40
55
70
85
Ambient Air Temperature (oC)
Iout
(A)
400 LFM (2.0 m/s)
300 LFM (1.5 m/s)
200 LFM (1.0 m/s)
100 LFM (0.5 m/s)
0 LFM (0 m/s)
Figure 7: Maximum output power derating curves vs. ambient air tem-
perature for airflow rates of 0 LFM through 400 LFM with air flowing
from input to output (nominal input voltage).
Product # PQ48018HTA60
Phone 1-888-567-9596
Doc.# 005-2HT418F Rev. O
11/20/02
Page 6
Figure 8: Thermal plot of converter at 52 amp load current with 55°C
air flowing at the rate of 200 LFM. Air is flowing across the converter
from input to output (nominal input voltage).
Figure 9: Turn-on transient at full load (resistive load) (10 ms/div).
Top Trace: Vout (0.5V/div)
Bottom Trace: ON/OFF input (5V/div)
Figure 10: Turn-on transient at zero load (10 ms/div).
Top Trace: Vout (0.5V/div)
Bottom Trace: ON/OFF input (5V/div)
Figure 11: Output voltage response to step-change in load current (50%-75%-50%
of Iout(max); dI/dt = 0.1A/s). Load cap: 15F, 450 m
ESR tantalum capacitor and
1F ceramic capacitor. Top trace: Vout (100mV/div), Bottom trace: Iout (20A/div).
Figure 12: Output voltage response to step-change in load current (50%-75%-50%
of Iout(max): dI/dt = 5A/s). Load cap: 480F, 15 m
ESR tantalum capacitor and
1F ceramic capacitor. Top trace: Vout (200mV/div), Bottom trace: Iout (20A/div).
Half
Brick
Performance Curves
48Vin 1.8Vout 60A
Semiconductor
junction
temperature
is
within
1
°C
of
sur
face
temperature