What Is the INA219? I2C Current/Power Sensor: Specs and Uses
The INA219 is a sensor that measures current, voltage and power over I2C. It computes current/power by measuring the drop across a high-side shunt plus the bus voltage (address 0x40, ~0–26 V). It is used for power-consumption and battery-current monitoring. Its difference from the ACS712: shunt-based, digital and precise at low current, but not isolated.
The INA219 is a sensor that measures current, voltage and power over I2C. It computes current and power by measuring the voltage drop across a high-side shunt resistor plus the bus voltage. For the concept, see what is a sensor · what is I2C.
What is the INA219 used for?
Power-consumption monitoring, battery/charge current measurement, solar panel/load profiling and energy-meter projects. You read the current via the shunt, plus the load's voltage and power, directly over I2C.
Specifications
| Parameter | Value |
|---|---|
| Measures | Current + bus voltage + power |
| Interface | I2C (address 0x40, configurable) |
| Bus voltage | up to 0–26 V (module) |
| Shunt | usually 0.1 Ω (on the module) |
Difference from the ACS712
The INA219 is shunt-based, high-side, digital (I2C) and precise at low current. The ACS712 is Hall-effect, isolated, analog and better where high current/isolation is needed. For precise low-current and direct digital reading, the INA219 is chosen.
Limitations
- Being shunt-based, there is shunt loss/heat at very high current.
- Not isolated (for high-voltage isolation use a Hall type).
Equivalents
- INA226: more precise, wider.
- ACS712: Hall-effect, isolated, analog.
- INA260: a version with an integrated shunt.
Find it in our catalog
Use the INA219 search.