| Feature | Details |
| Interface | I2C (Standard & High Speed) |
| Bus Voltage Range | 0V to +26V DC |
| Max Current | ±3.2A (with 0.1$\Omega$ shunt) |
| Max Power Output | 80W (Approx) |
| ADC Resolution | 12-bit |
| Sensing Type | High-Side (Current & Power) |
Product Description The INA219 (CJMCU-219) is a sophisticated, digital current and power monitoring module that communicates via the I2C protocol. Unlike simple analog current sensors, the INA219 handles both current and voltage measurements simultaneously, allowing it to calculate Real-time Power (Watts) internally. It uses a high-precision shunt resistor to measure current on the high-side (between power source and load), which prevents ground interference issues. It is a premium choice for battery fuel gauges, solar power monitors, and smart power distribution systems where accuracy and digital integration are essential.
Key Highlights
All-in-One Power Data: Provides current (Amps), bus voltage (Volts), and calculated power (Watts) over a single I2C bus.
No-Drift Accuracy: Features a high-stability internal reference and 12-bit ADC, ensuring consistent readings even as temperatures fluctuate.
Bi-Directional Sensing: Can measure current flowing in both directions, making it perfect for tracking both the charging and discharging of batteries.
Selectable I2C Addresses: Features solder pads to change the I2C address, allowing up to 4 INA219 modules to be used on the same microcontroller pins.
Minimal Power Loss: Equipped with a 0.1$\Omega$ precision shunt resistor, which introduces negligible voltage drop into your circuit.
Technical Specifications
Operating Voltage (VCC): 3V to 5V DC
Current Sensing Range: 0 to 3.2A (up to 400mA with high-resolution settings)
Bus Voltage Accuracy: 1% (Max) over temperature
Dimensions: 25.5mm x 22.3mm
Mounting: Standard 2.54mm pitch pins and screw terminals for high-current leads.
Installation Tip from Robogears To use this with an Arduino, we highly recommend the Adafruit INA219 library. Connect the module's I2C pins (SDA/SCL) to your microcontroller. For the current measurement, connect the Vin+ to your power source and Vin- to the positive terminal of your load. Safety Warning: Although the IC can handle up to 26V on the bus side, ensure the VCC pin (logic power) never exceeds 5V. If you need to measure currents higher than 3.2A, you can replace the onboard SMD shunt resistor with a lower value (e.g., 0.01$\Omega$), though this requires modifying the software scaling.
Note: This product is the INA219 sensor module. Header pins and terminal blocks may require soldering. Product images are for illustration purposes only.