The STC4054 is a constant current/constant voltage charger for single cell Li-Ion batteries. No external sense resistor or blocking diode is required and its ThinSOT package make it ideally suited for portable applications.
The STC4054 is designed to work within USB power specifications. An internal block regulates the current when the junction temperature increases, in order to protect the device when it operates in high power or high ambient temperature.
The charge voltage is fixed at 4.2V, and the charge current limitation can be programmed using a single resistor connectd between PROG pin and GND. The charge cycle is automatically terminated when the current flowing to the battery is 1/10 of the programmed value. If the external adaptor is removed, the STC4054 turns off and a 2µA current can flow from the battery to the device. The device can be put into Shutdown Mode, reducing the supply current to 25µA. The device also has a charge current monitor, under voltage lockout, automatic recharge. The device is packaged in TSOT23-5L.
- 25µA supply current in shutdown mode
- C/10 charge termination
- Soft-start limits inrush current
- Low battery voltage detect for precharge setting
- TSOT23-5L package
- Single charge status output pin
- Automatic recharge
- Programmable charge current up to 800mA
- Constant current / constant voltage operation with thermal regulation to maximize charge rate without risk of overheating
- No external MOSFET, sense resistors or blocking diode required
- Preset 4.2V charge voltage with 1% accuracy
- Charge current monitor output for gas gauging
- Charges single cell li-ion batteries directly from USB port