Charging skills of lithium battery charger

Lithium battery charger: The power circuit is composed of power transformer T, rectifier bridge reactor UR and filter capacitor C6. The charging control circuit is composed of an integrated circuit, resistors R1~R3, capacitors C1~C5, diodes VD1~VD3 and inductor L. The protection circuit is composed of fetVF, resistors R4, R5 and IC pin 5. After T step-down, UR rectification, and C6 filtering, the ac220V voltage appears +14V, which is supplied to the IC through VD1 and the protection circuit through VD1. The integrated circuit (SC1410A) is composed of oscillator, switch output circuit, PWM control and current/voltage control protection circuit. When the IC is excited, the internal oscillator oscillates an oscillating signal 500khz, and the output circuit of the switch is in an alternating high-frequency switching state. A constant charging voltage is output from the 10-pin (bat) rechargeable lithium battery GB of the IC. After the national standard is fully charged (the terminal voltage reaches 4.2v), the IC internal control protection circuit works, and the 10 pins have no voltage output, and the charging ends. If the input voltage is too high for some reason, VF is performed so that the voltage across R5 exceeds the reference threshold voltage of 2.465V, the internal protection circuit of the IC works, and there is no voltage output at 10 pins. Component selection R1~R5 selects 1/4w metal film resistors. C1~C3 all use monolithic capacitors; C4 and C5 are aluminum electrolytic capacitors with a voltage of 16V. C6 uses aluminum electrolytic capacitors with a voltage of 25V. Both VD1 and VD2 use 1N5819 Schottky diodes. VD3 uses 1N4148 silicon switching diodes. UR selects 2A, 50V rectifier bridge reactor. VF chooses NDS355N field effect transistor. The IC is charged by SC1410A dedicated IC. I choose TDK color code inductors. T uses a power transformer with a secondary voltage of 5W and 12V. Therefore, we should do a good job of charging lithium batteries, and have in-depth knowledge and mastery of the relevant principles and structural characteristics of lithium batteries and chargers. You cannot charge blindly. Disclaimer: Some pictures and content of the articles published on this site are from the Internet. If there is any infringement, please contact to delete.