INA219 DC current/voltage sensor

INA219 breakout pinout, high-side wiring for DC up to 26 V, the 0.1 Ω shunt and ±3.2 A range, I2C addresses 0x40–0x4F and calibration.

I2C

Community draft — report a mistake

CategorySensor

InterfaceI2C

Voltage3.0–5.5 V

Typical price₹180

3.3 V or 5 V? Power VCC from your board's logic voltage (3.3 V or 5 V); the I2C pull-ups go to VCC, so they match your board.

The INA219 measures DC current, bus voltage (up to 26 V) and power with 12-bit resolution. It sits on the high side — in series with the positive wire between source and load — and measures the tiny voltage across a 0.1 Ω shunt resistor, giving about ±3.2 A full scale.

It’s ideal for solar panels, battery packs, tower/router backup batteries and USB power profiling. With 16 possible addresses (A0/A1 pads), several can share one I2C bus.

DC only. It is not for mains: never connect it to 230 V AC.

Prices are indicative (Oct 2026) and vary by seller.

Pinout

Pin	What it does
`VCC`	3.0–5.5 V logic supply
`GND`	Ground (must be shared with the measured circuit)
`SCL`	I2C clock
`SDA`	I2C data
`VIN+`	Shunt input from the power source (+) — screw terminal
`VIN-`	Shunt output to the load — screw terminal

I2C address:0x400x410x440x45

Library

Adafruit INA219 by Adafruit
Arduino IDE → Library Manager → search the name above. Each guide lists the exact version we compile against.

Use it with

Common errors

Bus voltage reads 0 V

The INA219 measures bus voltage on VIN−, referenced to GND. The measured circuit's ground must connect to the module GND.

Current saturates around 3.2 A

That's the limit with the stock 0.1 Ω shunt. Fit a smaller shunt and recalibrate for more current.

Address not found

Default is 0x40; the A0/A1 solder pads move it (up to 16 addresses). Run the I2C scanner.