MB3883 Datasheet, PDF (21/39 Pages) Fujitsu Component Limited. – 6-ch DC/DC Converter IC With Synchronous Rectification for voltage step-up and step-down

MB3883
• After a CH6 soft start, when the CTL1, 2, CTL3, CTL4, and CTL5 terminals are driven high
The capacitor (Cs) connected to the CS terminal (pin 15) starts charging and the error amp provides a soft start
by comparing the CH1 to CH5 output voltage to the voltage at the CS terminal.
Input
CTL ( pin 20)
CTL1, 2 ( pin 21)
CTL3 ( pin 22)
CTL4 ( pin 23)
CTL5 ( pin 24)
Output
2V
VB ( pin 27)
C+IN6 ( pin 5)
CH6 output voltage
Vo6
VREF ( pin 16)
0.9 V
2.49 V
CS ( pin 15)
CH1 to CH3 output
voltage Vo1 to Vo3
CH4, CH5 output
voltage Vo4, Vo5
1.25 V
1.25 V
t
(1)
(3) (2) (4)
(5) (6)
(7)
(6)’ (7)’
(1) to (2)
(3)
(4) to (5)
(6) to (7)
(6)’ to (7)’
: CH6 soft start interval
: VREF Output start
: CH1 to CH3 soft start interval
: CH4, CH5 soft start interval
: CH4 (CH5) soft start interval (waveform) as CTL4 (CTL5) go “H”
from “L” during CH1 to CH3 soft start interval
Note : Each of the terminals CTL1,2, CTL3, CTL4, and CTL5 can be switched on or off independently. When any of
these CTL terminals is switched on, a soft start operation is provided as shown in the above timing chart.
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