MB39A114 Datasheet, PDF (24/54 Pages) Fuji Electric – DC/DC Converter IC for Charging Li-ion Battery

MB39A114
s ABOUT CONSTANT VOLTAGE CONTROL STATE DETECTION/
OVERVOLTAGE DETECTION TIMING CHART
In the constant voltage control state, the CVM terminal (pin 5) of the constant voltage control state detection
block (CV Comp.) outputs the “L” level when the voltage at the FB3 terminal (pin 15) of the error amplifier (Error
Amp3) becomes 2.6 V (Typ) or less.
When the DC/DC converter output voltage enters the state of the overvoltage higher than a setting voltage, the
voltage at FB3 terminal (pin 15) of the error amplifier (Error Amp3) becomes 1.3 V (Typ) or less. As a result, the
OVP terminal (pin 18) of the overvoltage detection block (OVComp.) outputs the “H” level.
Both of the CVM terminal and the OVP terminal are open-drain output forms :
Error Amp3 FB3
Error Amp2
Error Amp1 FB12
CV Comp. CVM
OV Comp. OVP
OUT
Constant current
control
Constant voltage
control
2.6 V CV Comp. VTHL
2.5 V
1.5 V
1.3 V OV Comp. VTHL
Overvoltage
State
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