MB39A132QN-G-ERE1 Datasheet, PDF (22/56 Pages) Fujitsu Component Limited. – ASSP For Power Management Applications (Rechargeable Battery) Synchronous Rectification DC/DC Converter IC for Charging Li-ion Battery

MB39A132
■ SETTING THE CHARGE VOLTAGE
The charge voltage (DC/DC converter output voltage) can be set by the input voltage to ADJ3 pin (pin 18)
and CELLS pin (pin 25). The ADJ3 pin can set charge voltage per cell. The value of charge voltage can be
freely set when the ADJ3 pin is connected to an external resistor. When the VREF level voltage or the GND
level voltage is input to the ADJ3 pin, the internal high-precision reference voltage set in advance can be
used. When the VREF level voltage or the GND level voltage is input to the CELLS pin, or the CELLS pin is
left unconnected, the number of series batteries can be set.
The correspondence between the ADJ3 pin, the CELLS pin and charge voltage (DC/DC converter output
voltage) is shown below.
ADJ3 pin Input Voltage
VREF pin
(ADJ3 ≥ 4.1V)
2.4 V ≤ ADJ3 pin ≤ 3.9 V
GND pin
(0 V ≤ ADJ3 pin ≤ 0.9 V)
External voltage setting
(1.1 V ≤ ADJ3 pin ≤ 2.2 V)
CELLS
pin
GND
OPEN
VREF
GND
OPEN
VREF
GND
OPEN
VREF
GND
Charge Voltage
8.4 V
12.6 V
16.8 V
8.7 V
13.05 V
17.4 V
8.0 V
12.0 V
16.0 V
4 × ADJ3 pin voltage
OPEN 6 × ADJ3 pin voltage
VREF 8 × ADJ3 pin voltage
Remarks
2 Cells × 4.20 V/Cell
3 Cells × 4.20 V/Cell
4 Cells × 4.20 V/Cell
2 Cells × 4.35 V/Cell
3 Cells × 4.35 V/Cell
4 Cells × 4.35 V/Cell
2 Cells × 4.00 V/Cell
3 Cells × 4.00 V/Cell
4 Cells × 4.00 V/Cell
2 Cells × 2 ×
ADJ3 pin voltage/Cell
3 Cells × 2 ×
ADJ3 pin voltage/Cell
4 Cells × 2 ×
ADJ3 pin voltage/Cell
• ADJ3 pin internal circuit
ADJ3
18
VA
Comparator_A
4.0 V
Comparator_B
2.175 V
2.1 V
2.0 V
Logic
circuit
2.3 V
Comparator_C
Selector
VA _{To Error Amp3}
1.0 V
22
DS04–27265–3E