This is a QC3.0 fast charging circuit, 5V, 9V, 12V output. The circuit of the secondary output terminal is as shown above. But I don’t know the principle of this place.
What is the circuit composed of D5, R48, R47, C22, R46 and U7?
Bradley Posté sur January 18, 2021
The imitation will know, most of them have problems.
Payton Posté sur January 18, 2021
QC3.0 relies on D+ and D- for handshake communication, and the voltage is the same. No matter how many volts are output, as long as the phone is removed, the output voltage will definitely become 5V, otherwise the charger has a problem.
Grayson Posté sur January 18, 2021
A very clever circuit.
When the winding voltage (absolute value) is lower than the output capacitor voltage, discharge.
Mohammed Posté sur January 18, 2021
The protocol chip controls the TL431 reference to adjust the output voltage, it is not difficult to understand it
