Deepsleep and Power Bank



  • Hello,

    After a test with our project, the SiPy went off. The SiPy is mounted on an Expansion board and is powered on via a Power Bank. The problem is that this power bank has a minimal current draw needed else it's shutting down after 30 sec.

    The capacity of the power bank is quite important and that's the reason why we didn't take a LiPo battery. When the program starts everything is fine but going into deep sleep reduces the current below this minimal currect draw and the Power Bank goes off.

    We tried attaching a LiPo, but I think the problem will still be the same, once the LiPo fully recharged, the Power bank will shut down and the application will shut down when the LiPo is empty.

    I saw some people doing a pulse generator to not let the power bank go off, but I was wondering if the same could work while in deepsleep?
    Is there another way to fix this problem? I'm open to every solution.

    Thanks in advance



  • @toppert
    Some of power banks can support low current mode. Some of tem must be turned in this mode by special press on the button, some work from the start. But many do not support low current mode at all.
    E.g. "Mi" power banks support this mode - but as @seb say already it is super inefficient.
    You can got longer time from battery then from powerbanks.



  • Thanks seb for your fast reply.

    I will try to disassemble the power bank and get the battery to see if this works better in a first time. We went for power banks at the beginning to make the SiPy last for a really long time, maybe batteries could be a better option.



  • @toppert

    You shouldn't use a USB power bank but instead directly connect a lipo battery to the JST-PH connector on the expansion board. The USB power bank will be ineffcient since you are wasting power stepping the battery voltage up to 5v then back down to 3.3v on the pycom module. It also has the issues like you described where it turns itself off.

    If the power bank really is the only way you can get the capacity you need then just disassemble it to get the battery out.



Pycom on Twitter