MB3881 Datasheet, PDF (20/40 Pages) Fujitsu Component Limited. – 8-ch DC/DC Converter IC with Synchronous Rectifier for Voltage Step-up and Step-down

MB3881
• When the CTL-2 (CTL-4) terminal is driven low (“L” level) after channels 1, 3, 4, and 8 have been soft-started
The capacitor (Cs) connected to the CS terminal (pin 32) starts being charged. The channel-2 (channel-7) output
voltage is soft-started by the error amplifier in proportion to the CS pin voltage.
Input
CTL-1 ( pin 28)
CTL-2 ( pin 29)
(CTL-4 ( pin 31) )
CTL-3 ( pin 30)
Output
2V
VB ( pin 36)
FB8 ( pin 4)
CH8 output voltage
VO8
VREF ( pin 24)
0.3 V
2.5 V
CS ( pin 32)
CH1, CH3, CH4
output voltage
VO1, VO3, VO4
CH2 (CH7) output voltage
VO2 (VO7)
CH5, CH6 output voltage
VO5, VO6
1.25 V
(1) (2)
(3) (4)
(5) (6)
1.25 V
t
(5)
(6)
(1) to (4)
(2) to (3)
(5) to (6)
(5)’ to (6)’
: Channel-1, 3, 4 soft start interval
: Channel-8 soft start interval
: Channel-2 (channel-7) soft start interval
: Channel-2 (channel-7) soft start interval (waveform) as CTL-2 (CTL-4) goes
“H” from “L” during channel-1, 3, 4 soft start interval
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