PowMeter is a shield that fits under your Nano board and monitors both USB and VIN voltage and current. I made this shield because every time I design and test an Arduino project I focus on its power consumption and it is not handy at all to use a couple of multimeters to monitor voltage and current plus it is not possible to log the values. PowMeter on the other hand is a "plug and play solution" that allows the host shield to query the measurements.

It is designed to be:

• A Very compact and lightweight solution. It adds only 23 mm in length to your circuit footprint.
• Versatile: USB monitoring goes to 0.8A with a 25 uA resolution, and VIN can hold 8A with a resolution of 250 uA.
• You can raise visual alerts as well as hardware alerts based on voltage or current under level or over level.

PowMeter comes with a special split cable that will allow to power your Host+Shield and program the Nano host at the same time i.e. one plug powers PowMeter and the other has only data lines to the host board. It was made specially for this application. Also included is a Nano clone board so you can start immediately to exploit the solution.

Features & Specifications:

• USB Power Monitoring Range: 0–500 mA (constant), 0-24 V. Resolution: 0.025 mA, 10 mV. Accuracy: ±1% current, ±1% voltage.

• VIN Power Monitoring Range: 0–6 A (constant), max 8 A (spike), 0-24 V. Resolution: 0.25 mA, 10 mV. Accuracy: ±1% current, ±1% voltage.

• OLED Display Display voltage and current for USB and/or VIN. Room for three to four digits. Display available for use by your application.

• I2C Interface Configure shield. Query measurement values.

Dimensions Size: 69 mm x 18.2 mm x 18.5 mm. Weight: 10 grams. Power USB connector: mini Type-B Current draw: ~10 mA.

A detailed presentation is available on Pandauino.com - PowMeter shield for Nano.