#The7thLiChuangElectricityContest#usb power meter

1. Introduction
This is a USB power meter based on N32G430C8L7+INA199, with a maximum input voltage of 25V and a maximum measurable current of 6A. It is equipped with a CH224K chip, and can achieve 5V, 9V, 12V, 15V, and 20V PD voltage spoofing through CC or USB2.0 differential lines. The circuit board is equipped with four interfaces, which can achieve bidirectional measurement from any male/female to any female/male. The signal line is differentially wired, and can be used as an interface converter for daily use.
 
2. Hardware
1. The PW2312 DC-DC chip is used as the main chip, PD spoofing chip and screen power supply
2. Two key switches are used to control the measurement current direction and PD spoofing respectively
3. The display part uses a 0.96-inch white OELD screen module, using IIC communication, and the display effect is clear.
4. Four-layer circuit board, thickness 1.0
 
3. Software part
1. Use three ADC converters to measure the voltage of the voltage divider resistor, the voltage converted by the INA199 chip, and the reference voltage of the INA199 chip
2. Use two interrupts to control the current direction and PD respectively
 
 
4. Finished product display
 
 
5. Explanation:
 
This project still has a lot of room for improvement. Voltage spoofing is not stable, and the accuracy has not been carefully discussed. It is only for practice and for reference only.