BQ55090ETA27 Datasheet, PDF (6/13 Pages) SynQor Worldwide Headquarters – Eighth-brick DC Bus Converter

Technical Specification
Input: 35-55 V
Output: 9.6 V
Current: 27 A
Package: Eighth-brick
25
20
15
400 LFM
10
300 LFM
200 LFM
5
100 LFM
0
25
40
55
70
85
Ambient Air Temperature (^oC)
Figure 7: Maximum output power derating curves vs. ambient air tem-
perature for airflow rates of 100 LFM through 400 LFM with air flow-
ing from output to input (nominal input voltage).
Semiconductor junction temperature is
within 1°C of surface temperature
Figure 8: Thermal plot of converter at 27 amp load current (250W)
with 55°C air flowing at the rate of 200 LFM. Air is flowing across the
converter from output to input (nominal input voltage).
Figure 9: Turn-on transient at full load (resistive load) (1.0 ms/div).
Input voltage pre-applied. Top Trace: Vout (2V/div). Bottom Trace:
ON/OFF input (1V/div).
Figure 10: Turn-on transient at zero load (1.0 ms/div). Top Trace: Vout
(2V/div). Bottom Trace: ON/OFF input (1V/div).
See Fig. 14
10 µH
source
impedance
See Fig. 13
See Fig. 15
i_S
V_SOURCE
i_C
47 µF,
<1W ESR
electrolytic
capacitor
DC/DC
Converter
V_OUT
1 µF 15 µF,
ceramic _{450mW ESR}
capacitor _tantalum
capacitor
Figure 11: Output voltage response to step-change in load current (50%-75%-
50% of Iout(max); dI/dt = 0.1A/µ s). Load cap: 15µ F, 100 mW ESR tantalum cap
and 1µ F ceramic cap. Top trace: Vout (200mV/div), Bottom trace: Iout (5A/div).
Figure 12: Test set-up diagram showing measurement points for Input
Terminal Ripple Current (Figure 13), Input Reflected Ripple Current
(Figure 14) and Output Voltage Ripple (Figure 15).
Product # BQ55090ETA27
Phone [phone]
www.synqor.com
Doc.# 005-2BE559C Rev. B
10/10/06
Page 6