ACE4054
Fully integrated constant current/constant voltage
Recharge Voltage vs Temperature
Li-ion battery charger
Trickle Charge Voltage vs Temperature
T (℃)
T (℃)
Detailed description
The ACE4054 is a single cell, fully integrated constant current (CC) / constant voltage (CV) Li-ion battery
charger. It can deliver up to 600mA of charge current with a final float voltage accuracy of
±1%.
The
ACE4054 has a build-in thermal regulation circuitry that ensures its safe operation. No blocking diode or
external current sense resistor is required; hence reduce the external components for a basic charger
circuit to two. The ACE4054 is also capable of operating from a USB power source.
Normal Charge Cycle
The ACE4054 initiates a charge cycle once the voltage at the VCC pin rises above the UVLO threshold
level. A 1% precision resistor needs to be connected from the PROG pin to ground. If the voltage at the
BAT pin is less than 2.9V, the charger enters trickle charge mode. In this mode, the charge current is
reduced to nearly 1/10 the programmed value until the battery voltage is raised to a safe level for full
current charging.
The charger switches to constant-current mode as the BAT pin voltage rises above 2.9V, the charge
current is thus resumed to full programmed value. When the final float voltage (4.2V) is reached the
ACE4054 enters constant-voltage mode and the charge current begins to decrease until it drops to 1/10
of the preset value and ends the charge cycle.
Programming Charge Current
The charge current is programmable by setting the value of a precision resistor connected from the
PROG pin to ground. The charge current is 1000 times of the current out of the PROG pin. The program
resistor and the charge current are calculated using the following equations:
The charge current out of the BAT pin can be determined at any time by monitoring the PROG pin
voltage using the following equation:
VER 1.4
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ACE [ ACE TECHNOLOGY CO., LTD. ]
