TP4057  (500mA linear lithium-ion battery charger) NanJing Top Power ASIC Corp describe TP4057 is a complete single section lithium-ion battery charger with positive and negative polarity reverse protection, using constant charge Linear control of flow/constant voltage. Its SOT packaging and fewer external components make TP4057 portable applications more efficient Want to choose. TP4057 can be suitable for USB power supply and adapter power supply operation. Due to the use of an internal PMOSFET architecture and an anti backcharging circuit, there is no need for external detection resistors and Isolation diode. Thermal feedback can automatically adjust the charging current for high-power operation or high ambient temperature conditions Lower the temperature limit on the chip. The full charge voltage is fixed at 4.2V, while the charging current can be externally controlled through a resistor Settings. When the battery reaches 4.2V and the charging current drops to 1/10 of the set value, TP4057 will automatically terminate charging. When the input voltage (AC adapter or USB power supply) is removed, TP4057 automatically enters a low current state State, the battery leakage current is below 2uA. Other features of TP4057 include charging current monitor, undervoltage lockout, and self Dynamic recharge and two status pins used to indicate the end of charging and input voltage connection characteristic ·Lithium battery positive and negative polarity reverse protection; ·Programmable charging current up to 500mA; ·No need for MOSFETs, detection resistors, or isolation diodes; ·For single lithium-ion batteries ·Constant current/constant voltage operation, with the ability to operate without overheating risk Thermal regulation function to maximize charging rate in case of danger; ·Single lithium-ion batteries can be charged directly from the USB port; ·4.2V preset charging voltage with an accuracy of ± 1%; ·The maximum input can reach 9V; ·Automatic recharge; ·2 charging state open drain output pins; ·C/10 charging termination; ·The power supply current in standby mode is 40uA; ·2.9V Trickle Charger Component Version; ·Soft start limits surge current; ·It is packaged in a 6-pin SOT-23 package. application ·Charging stand ·Cellular phone, PDA, MP3 player ·Bluetooth applications Typical Applications 500mA single lithium-ion battery charger Absolute maximum rating ·Input power voltage (VCC): -0.3V~9V ·PROG: -0.3V~VCC+0.3V ·BAT: -4.2V~7V ·CHRG: -0.3V~10V ·BAT short-circuit duration: continuous ·BAT pin current: 500mA ·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 ℃