SparkFun Power Meter - ACS37800 (Qwiic)

The SparkFun Power Meter is a comprehensive power sensing solution built around the Allegro ACS37800 power monitor IC. Designed to slide seamlessly into your next Qwiic project, this board allows you to monitor voltage (up to 60VDC) and current (up to 30A) simultaneously without cutting traces or managing complex wiring. It is the perfect tool for tracking power consumption in high-demand systems like 3D printers, UAVs, and solar panels.

Isolated & Efficient Power Monitoring

Unlike traditional sensors that rely on hot, inefficient shunt resistors, the ACS37800 uses Hall-effect technology to measure current.

• Cool Operation: Because there is no shunt resistor, there is no heat generation or voltage drop, meaning the sensor itself doesn't waste the power it is trying to measure.
• Galvanic Isolation: The internal construction provides reinforced isolation between the current-carrying conductor and the sensing electronics, keeping your logic-level microcontroller safe from the high-current path.

Smart Monitoring

This chip does more than just read raw numbers. It offers key power parameters accessed directly through its I²C interface:

• Complete Data: Reads Voltage, Current, and Power simultaneously.
• Onboard Intelligence: Features dedicated pins for zero-crossing detection and fast overcurrent fault reporting.
• Configurable: You can adjust settings like over/under-voltage thresholds directly via the Qwiic interface and save them to the chip’s onboard EEPROM.

Is This the Right Power Meter for You?

While the ACS37800 Qwiic Power Meter is excellent for heavy loads, including motor control, battery charging, solar arrays, and devices drawing less than 1 Amp, it is not suitable for low-current applications such as microcontrollers in sleep mode, single LEDs, or applications requiring milliamp-level precision. The ACS37800 has a noise floor of approximately ±0.1A RMS on its current channel.

• Schematic
• Eagle Files
• Datasheet (ACS37800)
• SparkFun Arduino Library
• GitHub Hardware Repo