Nordic Power Profiler Kit II
One of the most critical challenge of embedded systems is managing the power budget. And very often, measuring power consumption turns into another major challenge.
I have already reviewed proprietary solutions like EnergyTrace, albeit optimised for Texas Instruments silicon, and more general tools like the volt-amp-watt-meter based on the INA219.
Nordic comes with an interesting option: a universal ammeter with 8 logic inputs.
The installation of the software requires two steps:
Good point, the source code is open source and available at a GitHub repository. It is also platfrom agnostic and runs on Linux, Mac and Windows.
However, on Linux, the device was listed with lsusb but wasn't detected by the Power Profiler application. The documentation doesn't mention that Linux computers require an additional step:
The ammeter operates in two different modes:
One the device has been selected and the mode set, the left pane offers other parameters, like the voltage to be supplied in source mode, the number of samples per second, up to 100 k, the duration, and the logic channels to monitor.
The RGB LED adapts its colour to the selected mode:
Surprisingly, the documentation doesn't mention the meaning of the different colours.
1 C Coulomb = 1 A Ampère × 1 s second
Additionally, the device can record up to 8 logic signals. This is a great way to identify parts of an application. Alas, there is no option to use those logic inputs as triggers, for example to start or stop the trace.
The connections are:
In the example pictured, the device is configured on source mode and the USB cable supplies the power.
At around EUR100, the Nordik Power Profiler II offers an insteresting solution for measuring power consumption of embedded systems.
The 8 logic inputs allow to set markers on the code to identify the specific parts of the applications under review.
The limitations I have experienced (incomplete procedure, lack of trigger feature) could be easily solved by updating the documentation and the software.
Posted: 15 Apr 2022