describe

SC4054 is a complete single lithium-ion battery with a constant current/voltage linear charger. Its SOT package and fewer external components make SC4054 an ideal choice for portable applications. SC4054 is suitable for USB power supply and adapter power supply. Because of the internal PMOSFET architecture and anti-backcharging circuit, there is no need for external detection resistors and isolation diodes. Thermal feedback can adjust charging current to limit chip temperature under high power operation or high ambient temperature. The charging voltage is fixed at 4.2V, and the charging current can be set externally by a resistor. When the charging current drops to 1/10 of the set value after reaching the final floating charging voltage, SC4054 will automatically terminate the charging cycle. When the input voltage (AC adapter or USB power supply) is removed, SC4054 automatically enters a low current state, reducing the leakage current of the battery to less than 2uA. SC4054 can also be placed in shutdown mode to reduce the supply current to 45uA. Other features of SC4054 include charging current monitor, undervoltage blocking, automatic recharging and a status pin for indicating charging end and input voltage access.

Characteristic

Programmable charging current up to 800 mA; no need of MOSFET, detection resistor or isolation diode; complete linear charger for single lithium-ion battery packaged with SOT 23-5; constant current/constant voltage operation, and thermal regulation function to maximize charging rate without overheating risk; direct from USB port to single lithium ion Battery charging; 4.2V preset charging voltage with accuracy of 1%; output of charging current monitor for battery power detection; automatic recharging; output pin of charging state; C/10 charging termination; 45 uA supply current in standby mode; 2.9V trickle current charging device version; soft start restricts surge current; 5-pin SOT-23 package is adopted.

Absolute maximum rating input power supply voltage (VCC): - 0.3V 10V PROG: - 0.3V VCC + 0.3V BAT: - 0.3V 7V 0.3V 10V BAT short circuit duration: continuous BAT pin current: 800mA PROG pin current: 800uA maximum junction temperature: 145 working environment temperature range: - 40 85 storage temperature range: - 65 125 pin temperature (welding). Time: 10 seconds: 260 degrees Celsius

Applications: Cellular Phone, PDA, MP3 Player, Charging Seat, Bluetooth Application.

A typical 400 mA single lithium-ion battery charger