MAX32660 Evaluation Kit - part 4c: Low Power Sensor design - Barometer, Not Yet Power Optimised

RE: MAX32660 Evaluation Kit - part 4c: Low Power Sensor design - Barometer, Not Yet Power Optimised

Jan Cumps — Fri, 21 Dec 2018 19:13:17 GMT

I bricked the device when uploading my first low power design. It's a subset of the low power design from Maxim.

i don't know why the controller is stuck - there was a mix of a SDK update from Maxim gone wrong and me adapting a working project to low power.

Chances are that I put it in a state that's not reacting on the debugger.

For the heroes, I've attached a project to this blog called donttryathome_roadtest_project_optimise.zip.

It is source code and binary. After I uploaded it the device is bricked. My ask is to not try it at home, but maybe look at my code and see if you see a problem.

RE: MAX32660 Evaluation Kit - part 4c: Low Power Sensor design - Barometer, Not Yet Power Optimised

Jan Cumps — Fri, 21 Dec 2018 08:03:59 GMT

This is the consumption with the printf functions removed and the UART module switched off.

[embed:dc8ab71f-3b98-42d9-b0f6-e21e02a0f8e2:3ef06e6b-9b7d-4651-b12d-db8be7f5e991:type=c_cpp&text=SYS_ClockDisable%28SYS_PERIPH_CLOCK_UART0%29%3B]

[View:/resized-image/__size/556x333/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-e710f34b-9640-4e2b-9f28-2611bcec8baa/4113.contentimage_5F00_189779.png:556:333]

I'll use a setting of 10 mV / div going onward, because I can get that on the screen, including the noise.

Because the integral and the area figures are calculated from onscreen data, it's key to get all the noise on screen.

That way, the positive side cancels out the negative in these calculations.

Because the µCurrent used for measurement, a mV on the oscilloscope represents a mA flowing to the microcontroller.

RE: MAX32660 Evaluation Kit - part 4c: Low Power Sensor design - Barometer, Not Yet Power Optimised

Jan Cumps — Tue, 18 Dec 2018 19:44:26 GMT

Note to @self: low power measurements are hard. Use everything the same when measuring.

I was getting lower power measurements today. There's a difference if I power this from my laptop or a USB brick. (almost 50% - go figure)

RE: MAX32660 Evaluation Kit - part 4c: Low Power Sensor design - Barometer, Not Yet Power Optimised

DAB — Mon, 17 Dec 2018 21:03:20 GMT

Nice update Jan.

DAB