PJ4057

PJ4057 Linear Lithium-ion Battery Charger Description PJ4057 is a complete single lithium ion battery with constant current/constant voltage linear charger. Its SOT package and small number of external components make the PJ4057 ideal for portable applications.PJ4057 can be suitable for USB power and adapter power supply work. Due to the internal PMOSFET architecture, plus the anti-inverted charging circuit, there is no need for external detection resistor and isolation diode. Thermal feedback adjusts the charging current to limit chip temperature at high power operation or ambient temperature conditions.The charging voltage is fixed at 4.2V, and the charging current can be set externally through a resistor. When the charging current reaches the final floating charging voltage and drops to the set value of 1/10,PJ4057 will automatically terminate the charging cycle. When the input voltage (ac adapter or USB power supply) is removed, PJ4057 automatically enters a low current state, reducing the battery leakage current below 2uA.PJ4057 can also be placed in stop mode to reduce the power supply current to 25uA.Other features of the PJ4057 include a charging current monitor, undervoltage latching, automatic recharging, and a status pin to indicate the end of charging and input voltage access. Dual light indicator for chip integrated charging status, which can be configured to light the red light when charging, and the green light after charging. Features  500mA programmable charging current;  No MOSFET, test resistor or isolation diode required;  A complete linear charger with SOT-23-6 package for single lithium ion battery;  Constant current/voltage operation, with thermal regulation function;  Charge single lithium ion battery directly from USB port;  4.2V charging voltage is preset;  Output of charging current monitor for battery quantity detection;  1/10 Charge termination, automatic recharging;  Power supply current in standby mode is 25uA;  Soft boot limits the surge current;  2.9V trickle charge device version Rprog resistance and charging current Ibat corresponding table Applications Rprog Ibat Ibat=1000/Rprog PJ4057 www.pingjingsemi.com Revision:1.0 May-2019 10K 100mA 5K 200mA 3.3K 300mA 2.5K 400mA 2K 500mA 1.65K 600mA 1/5 PJ4057 Linear Lithium-ion Battery Charger Pin Distribution 1.CHRG 2.GND 3.BAT Pin Function CHRG(Pin1) SOT-23-6 6.PORG 5.STBY 4.VCC Output of open drain charging state. The CHRG pin is pulled to low level by an internal N-channel MOSFET during battery charging. When the charging cycle ends, CHRG pin is off and all lights are off. When PJ4057 detects an under voltage blocking condition, the CHRG pin is forced to a high impedance state. GND(Pin2) GND BAT(Pin3) Charging current output.The pin provides charging current to the battery and adjusts the final floating charging voltage to 4.2V. A precise internal resistance voltage divider of the pin sets the floating charging voltage. In the shutdown mode, the internal resistance voltage divider is disconnected. VCC(Pin4) Positive input power voltage.This pin supplies power to the charger.VCC shall vary from 4.25V to 6.5V and shall be bypassed by at least one 1uF capacitor.When the VCC drops to less than 30mV of BAT pin voltage,PJ4057 enters the stop mode, and the Ibat falls below 2uA. STBY(Pin5) PROG(Pin6) www.pingjingsemi.com Revision:1.0 May-2019 The charging status indicates that when the battery is charged, STDBY is pulled to a low level by an internal switch to indicate the end of charging. In other states, STDBY pins are in a high impedance state Charging current setting, charging current monitoring and stop pin.The charging current can be set by connecting a 1% precision resistor Prog between the pin and the ground.When charging in constant current mode, the voltage of this pin is maintained at 1V. In all modes, the voltage on this pin can be used to calculate the charging current. The formula is Ibat=(Vprog/Rprog)*1000.Short connect the set resistor to the ground, and an internal 2uA current pulls the PROG pin to a high level.When the voltage of this pin reaches the stop threshold voltage of 1.21V, the charger enters the stop mode, the charging stops and the input power current drops to 25uA.The clamping voltage of this port is about 2.4V.Supply this port with a voltage in excess of the clipping voltage and a high current of 1.5 mA will be obtained,Reconnecting the Rprog to the ground will restore the charger to normal operation. 2/5 PJ4057 Linear Lithium-ion Battery Charger Absolute Maximum Rating Input Voltage VSS-0.3V～VSS+7V PROG VSS-0.3V～VSS+0.3V BAT VSS-0.3V～VSS+7V CHRG VSS-0.3V～VSS+10V BAT short-circuit period Continue BAT Pin Current 500mA PROG Pin Current 800uA -40℃～85℃ Operating Temperature Range Storage Temperature -65℃～125℃ Pin temperature (welding time: 10s) 260℃ Block Diagram 4 VCC 120℃ TDIE TA 1X 1000X BAT 5μA MA 3 R1 VA CA SHDN R2 C1 REF 1.21V R3 1V R4 1 0.1V C2 CHRG R5 STANDBY 3μA C3 TO BAT 2.9V VCC 5 www.pingjingsemi.com Revision:1.0 May-2019 GND PROG RPROG 2 3/5 PJ4057 Linear Lithium-ion Battery Charger Electrical Characteristics (TA =25℃ unless otherwise specified.) Parameter Symbol Input Voltage VCC Input Current ICC Min. Typ. 4.2 charging mode，Rprog=10K 5 300 standby mode(Charge termination) 50 150 25 50 Test Condition stop mode(RPROG ununited) VCC