The INA219 breakout board can be powered by the 5V or 3V pin on your Arduino and communicates via I2C.
Connect to the microprocessor
Next we must insert the INA219 current sensor into the circuit we want to measure:
- Connect V+ to the positive terminal of the power supply for the circuit under test.
- Connect V- to the positive terminal or lead of the load. This puts the sense resistor in-line with the circuit.
- Finally, connect a wire from the negative terminal of the power supply to GND. This allows the sensor to measure the load voltage as well as the load current.