Overview：

The TC4056A is a complete single-cell lithium-ion battery charge management chip with built-in battery polarity reverse protection and resistance to positive/negative pulse冲击. It features constant current/constant voltage linear control for charging. Its ESOP8 package and minimal external component count make the TC4056A an ideal choice for portable applications. The TC4056A can operate from both USB power and adapter power sources. Thanks to its internal PMOSFET architecture and anti-reverse current circuit, no external sense resistor or isolation diode is required. Thermal feedback automatically regulates the charge current to limit the die temperature during high-power operation or at high ambient temperatures. The float voltage is fixed at 4.25V, while the charge current can be programmed externally via a single resistor. When the battery voltage reaches 4.25V and the charge current drops to 1/10 of the programmed value, the TC4056A automatically terminates charging. When no charger power is present, the TC4056A automatically enters a low-current state, drawing less than 2µA of battery leakage current. Additional features include charge current monitoring, undervoltage lockout, auto-recharge, and two open-drain output pins for charging status and input power indication.

Features：

Lithium battery polarity reverse protection and resistance to positive/negative pulse冲击

0V battery charging activation

Programmable constant output charge current up to 1000mA

Dual-LED status display with battery polarity detection capability

No external MOSFET, sense resistor, or isolation diode required

Designed for single-cell lithium-ion battery charging

Constant current/constant voltage operation with thermal regulation that maximizes charge rate without risk of overheating

Can be powered directly from USB ports for single-cell lithium-ion battery charging

Preset 4.25V charge voltage with ±1% accuracy

Auto-recharge function

Two open-drain charge status output pins

C/10 charge termination

40µA supply current in standby mode

Soft-start limits inrush current

Available in thermally enhanced ESOP8 package

Applications：

Various single-cell lithium battery chargers

LED headlamp USB charging cables

E-cigarette chargers

Handheld fans