Figure 3: One kind of maximizing charge current thermal

regula�on circuit mode

CC

A

can be full scale output 800mA charging current at higher

ambient temperatures.

Although this applica�on can deliver more energy to the

ba�ery in heat regula�ng mode and shorten the charging

�me, But in voltage mode, if VCC becomes low enough

leaving FC9054 state at low voltage drop, It is actually

possible to extend the charging �me. Figure 4 shows how

When in order to maintain a smaller component size and to

technology can play a role in the best. Keep in mind: you

should select a sufficient power handling capability resistor.

Figure 4: Charging current rela�onship with the RCC curve

Automatic restart

Once the charge cycle is terminated, FC9054 immediately

adopt a comparator with 1.8ms filter �me con�nuously

monitor the BAT pin voltage. When the ba�ery voltage

drops below 4.05V or less (Generally corresponding to the

ba�ery capacity from 80 to 90%), charging cycle restart.

This ensures that the battery is maintained at (or near) a

full charge state, and eliminates the periodic need to

start charging cycle. A typical charge cycle state

diagram is shown below.

Shut down mode

CHRG=High impedance

Precharge mode

CHRG=LOW

Constant current charge mode

CHRG=LOW

Constant voltage charge mode

Charge voltage=4.2V

CHRG=LOW

Charge end

No charge current

CHRG=High impedance

FC9054

FC9054

2019. 05. 13

7/8

Revision No : 0