SparkFun Current Sensor - INA237 (Qwiic)

The SparkFun INA237 Qwiic Current Sensor makes it easy to monitor DC current and power with high precision over I²C. This Qwiic breakout features the INA237 digital power monitor from Texas Instruments, which measures current, bus voltage, temperature, and power for an in-line DC input using a 16-bit delta-sigma analogue-to-digital converter (ADC).

Solderless or Soldered Integration

The INA237 Current Sensor includes both a 3-pin screw terminal and a pair of Qwiic connectors to allow for a solderless power monitor setup using the Qwiic ecosystem. A 15 mΩ shunt resistor comes pre-populated on the board, but we've also provided through-hole pins for a custom shunt resistor value if needed! Keep in mind that this board shares the same physical design as our INA228 breakout and with the specific version noted by the box in the top left corner of the board.

For those who prefer a soldered connection, the breakout features a 0.1"-spaced plated through-hole header that breaks out the INA237's power, communication pins (SDA/SCL), and alert pin. The alert pin is a multi-purpose open-drain digital output that can report when conversions complete or when the INA237 measures values beyond a defined threshold, such as over/under voltage (both shunt and bus), along with exceeding current/power and temperature values. So, regardless of your preferred wiring method, integrating high-precision power monitoring into your project is as straightforward as possible!

Advanced Alerting and Measurement

The on-board INA237 has been specifically designed to offload heavy processing from your microcontroller, and features a multi-purpose open-drain alert pin that can report when conversions complete or when measurements exceed user-defined thresholds. To get the most out of your code, the INA237 offers several programmable hardware features:

• Threshold Alerts: Triggers that instantly alert you if voltage, current, power, or internal temperature values exceed your programmed limits.
• Fast Response: A rapid 75 microsecond alert response time to protect your sensitive electronics.
• Flexible Sampling: Selectable ADC conversion times from 50µs to 4.12ms and hardware averaging from 1 to 1024 samples.

By utilising these built-in hardware capabilities, your main processor can remain in a low-power sleep state until an actual power event requires its attention.

• Schematic
• KiCad Files
• Board Dimensions
• Hookup Guide
• Datasheet (INA237)
• SparkFun INA2XX Arduino Library
• GitHub Repository