Disable DC-DC 3.3v

  • Is it possible to disable the 3.3v regulator during deepsleep mode?. I have a current drain when a microSD is inserted and deepsleep mode is activated (around 5mA), because it is powered by 3.3v pin. If the SD is removed, the current drain stops (20uA).

    I am using a Wipy3 with lastest firmware and expansion board 2.1.
    Any ideas?

  • @livius Agreed. I was going to use an SD Card to store config, state and logs, but now my device is no longer low power...

    Seems a bit off when you can switch all (that I know of) bit off.

  • Thanks for the information.

    However, in my opinion, the control of the 3.3V Dc pin should be a important feature included in the Pycom device. My design sources several sensors using the 3.3V and, obviously, the current drained in deep sleep mode makes difficult the power autonomy.

    I have shorcutted the problem using a PNP transistor BCW68 and a 3,9K resistor in its base. It is controlled by a GPIO Pin. The emissor Pin goes to the WiPy 3.3v Pin and collector Pin is connected to the sensors and the SD card.

  • then it is another design bug?

  • @roqueton
    It's not possible, sorry. As you have found the microSD card slot is always powered.

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