High current consumption in sleep, Why ?

[JF002]

Before the measurements I switched off the lcd and the nrf52 with SD too with the :  lcd.sendCommand(0x10);  and sd_power_system_off();

The difficulty here is that the MCU will automatically wakes up for any reason (event, irq, timer,...), and it's not easy to know when it wakes up and why.

I measured the  standalone cpu with the same software as use in Pinetime, so I think the additional current comsuption is coming from additional chips and components, 800uA instead of 2uA !

It's possible that the devices on board (heart-rate sensor, motion sensor, SPI flash,... ) need to be put to sleep as well. I've noticed that at least the SPI flash and the LCD have a command to go to sleep mode.

I downloded your pinetime sw, "JF002_pinetime-app-full.hex" to Pinetime, and I measured it, when run it  needs 25mA, and in sleep mode needs 1.6mA.

That's interesting! As I said, a previous version of my firmware ran for nearly 7 days on battery. But the stock firmware performs better, and I did a lot of additions and modifications in the code since then. And... I do not have the equipment to measure the actuel power usage of my code.

If you want to debug my firmware and find why it's using so much power, feel free to send me the info or a PR

Also, Atc1441 (on twitter and on the pinetime chat rooms) manage to do some work on power usage : https://twitter.com/atc1441/status/1260534075456192517 You could have a look to his code or reach him in the chat!