ACE4704
Fully 5A, 4cell Standalone Li-ion Battery Charger
The TEMP pin’s pull up current is about 50uA, so the NTC thermistor’s resistance should be 10kΩ at
25℃, about 3.5kΩ at hot temperature threshold, and about 32kΩ at cold temperature threshold. The NTC
thermistor such as TH11-3H103F, MF52(10 kΩ), QWX-103 and NCP18XH103F03RB can work well with
ACE4704. The above mentioned part numbers are for reference only, the users can select the right NTC
thermistor part number based on their requirements.
If battery temperature monitoring function is not needed, just connect a 10KΩ resistor from TEMP pin to
GND.
Status Indication
The ACE4704 has 2 open-drain status outputs: CHRG and DONE. CHRG is pulled low when the
charger is in charging status, otherwise CHRG becomes high impedance. DONE is pulled low if the
charger is in charge termination status, otherwise DONE becomes high impedance.
When the battery is not present, the charger charges the output capacitor to the regulation voltage quickly,
then the BAT pin’s voltage decays slowly to recharge threshold because of low leakage current at BAT pin,
which results in a ripple waveform at BAT pin, in the meantime, CHRG pin outputs a pulse to indicate that
the battery’s absence. The pulse’s frequency is around 10Hz when a 10uF output capacitor is used.
The open drain status output that is not used should be tied to ground.
The table 1 lists the two indicator status and its corresponding charging status. It is supposed that red
LED is connected to CHRG pin and green LED is connected to DONE pin.
CHRG Pin
DONE pin
High Impedance (the green
LED off)
State Description
Low (The red LED on)
Charging
High Impedance (the red
LED off)
Low (the green LED on)
Pulse signal
Charge termination
Pulse signal
Battery not connected
There are three possible state:
The voltage at the VCC pin below the
UVLO level
The voltage at the VCC pin below VBAT
Abnormal battery’s temp
High Impedance (the red
LED off)
High Impedance (the green
LED off)
Table 1 Indication Status
VER 1.2
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ACE [ ACE TECHNOLOGY CO., LTD. ]
