Hello everyone,
I am using the Power Profiler Kit II (PPK2) to measure the deep sleep current of an ESP32-H2 when running the boilerplate OpenThread deep sleep SED program, as Espressif recommends the PPK2 as one of the devices to be used when measuring the current of their microcontrollers. However, when measuring the current of the ESP32-H2 under deep sleep, I get inaccurate measurements that are way off, compared to what should be expected.
In my initial measurements using the PPK2, the deep sleep current is recorded at ~1.2 mA:
However, the expected deep sleep current should be 7 uA, as can be shown in Espressif's measurements when using the Joulescope, and according to page 34 of the ESP32-H2 datasheet.
After some investigation and changing my measurement setup (as I described in my question in the official Espressif forums), I was able to get the PPK2 to measure much closer (but not quite at 7 uA), at approximately ~7.86 uA.
Although the measurement is much closer, it is still not as close as the ~7.6 uA average measured by Espressif. As a result, I do not whether or not the deep sleep measurement is accurate.
Given that this is an issue involving the ESP32-H2, I initially asked for help in the official ESP32 forums first. However, the administrator of the forums told me that they would not be able to help me fix the issues I have been having with my current measurements. As a result, I am asking my questions here, in the NRF forums, especially since I am using the PPK2 for my measurements.
With that being said, my questions are as follows:
- I am getting a consistent average of 7.8 uA for my deep sleep measurements. However, page 34 of the ESP32-H2 datasheet states that the current should be at 7 uA, and Espressif's measurements on the Joulescope has an average of ~7.6 uA. I have done multiple trials, and the PPK2 never measures below 7.8 uA. As a result, I would like to ask if this slightly inaccurate measurement on the PPK2 indicates that there still might be a problem with my measurement setup, or if if the PPK2 inaccuracy is due to potential noise?
- How do I properly set up the PPK2 to properly measure an ESP32-H2 device? To the best of my knowledge, there exists no tutorials and guides on how to do so. There was this tutorial on how to do so for ESP32 devices in general, along with this snippet in a PPK2 review video, but they do not describe how to do so for the ESP32-H2 in particular. I tried to adapt the guidance both tutorials gave for the ESP32-H2, but when doing so, I end up with the inaccurate deep sleep measurements. It was only through trial and error & reading through the documentation in which I found a solution that might work, which gave me the ~7.8 uA deep sleep current. Even then, I'm still unsure if I did my setup correctly.
Although this may be out of scope as it involves the use of a 3rd party ESP32 device, but any guidance, advice, and feedback on how I can head in the right direction would greatly be appreciated.
