ACE4559P

150mA Single Cell Li-ion Battery Charger, 0.1mA Termination, 45nA Battery leakage Current

VER 1.1

10

Operation Information

The ACE4559P is a single cell Li-Ion and Li-Pol battery linear charger using a constant-current /

constant-voltage algorithm. It is designed specially for small capacity battery that is used in handheld

devices, such as GPS tracker, Smart wrist and U-Key. It can deliver up to 150mA of charge current (using

a good thermal PCB layout) with a final float voltage accuracy of ±1%. The ACE4559P includes an

internal P-channel power MOSFET and current regulation circuitry. No blocking diode or external current

sense resistor is required, thus the basic charger circuit requires only two external components.

Furthermore, the ACE4559P is capable of operating from a USB power source.

Normal Charge Cycle

A charge cycle begins when the voltage at the VCC pin rises above the UVLO threshold level and a 1%

program resistor is connected from the PROG pin to ground or when a battery is connected to the charger

output. If the BAT pin is less than 2.9V, the charger enters trickle charge mode. In this mode, the

ACE4559P supplies approximately 1/10 the programmed charge current to bring the battery voltage up to

a safe level for full current charging.

When the BAT pin voltage rises above 2.9V, the charger enters constant-current mode, where the

programmed charge current is supplied to the battery. When the BAT pin approaches the final float

voltage, the ACE4559P enters constant-voltage mode and the charge current begins to decrease. The

charge cycle ends when the PROG voltage is less than 100mV.

Programming Charge Current

The charge current is programmed using a single resistor from the PROG pin to ground. The battery

charge current of constant current mode is 100 times the current out of the PROG pin. The program

resistor and the charge current of constant current are calculated using the following equations:

=1KΩ, I

Ω. Please choose 1% precision resistor for

Charge Termination

A charge cycle is terminated when the charge current falls to 1/10 of the programmed value after the final

float voltage is reached. This condition is detected by using an internal, filtered comparator to monitor the

is terminated. The charge current is latched off and the ACE4559P enters standby mode, where the input

supply current drops to 70uA. (Note: 1/10 CC termination is disabled in trickle charging mode).