Battery fast charging control integrated circuit design

　　Circuit principle: The circuit provides +5V power supply voltage by a transformer, diode and voltage regulator IC7805. The battery voltage is divided by resistors R5 and R6 and then sent to the BAT end of the chip to provide a sampling voltage. The resistance of the resistor voltage divider network input to the BAT terminal should not be less than 200kΩ. When the TM terminal is grounded, the corresponding fast charge charging rate is 1C and the fast charge replenishment time is 80 minutes.