MB39A119 Datasheet, PDF (18/53 Pages) Fujitsu Component Limited. – DC/DC Converter IC of Synchronous Rectification for charging Li-ion battery

MB39A119
3. Detection Functions
(1) AC adapter voltage detection block (AC Comp.)
When ACIN terminal (pin 4) voltage is lower than 2.0 V (Typ) , AC adapter voltage detection block (AC Comp.)
outputs “Hi-Z” level to the ACOK terminal (pin 5) and outputs “L” level to the XACOK terminal (pin 22) . When
CTL terminal (pin 21) is set to “L” level, ACOK terminal (pin 5) and XACOK terminal (pin 22) are fixed to “Hi-Z” level.
AC adapter detection function table
The logic of the following terminal is fixed according to the connection state of the AC adapter.
ACIN
ACOK
XACOK
H
L
Hi-Z
L
Hi-Z
L
(2) Constant voltage control state detection block (CV Comp.)
When CV Comp. detects that the FB123 terminal (pin 14) voltage of the error amplifier (Error Amp3) output
terminal becomes 2.6 V (Typ) or less, “L” level is output to constant voltage control state detection block output
terminal CVM terminal (pin 6) .
Charge control state function table
Error Amp3 output (FB123)
> 2.6 V
≤ 2.6 V
CVM
Hi-Z
L
Status
Constant current control
Constant voltage control
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