Welcome to the Pycom forum Forum
    • \[\[global:header.categories\]\]
    • \[\[global:header.recent\]\]
    • \[\[global:header.tags\]\]
    • \[\[global:header.popular\]\]
    • Login

    Explore Pybytes | Official Documentation | Report a Firmware Bug/Issue | GitHub

    Powering through VIN while USB is connected at the same time

    Scheduled Pinned Locked Moved Comments & Feedback
    vinusbpower
    5 Posts 5 Posters 57 Views 5 Watching
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as topic
    Log in to reply
    This topic has been deleted. Only users with topic management privileges can see it.
    • N Offline
      Nunya Bidness
      last edited by

      Hello everybody!

      I am using the LoPy4 microcontroller in combination with Expansion Board 3.0. My project requires occasional serial readings (connection via USB) while the board is being fed by a 1S LiPo. Due to specific requirements, the LiPo battery is connected directly to VIN rather than the onboard PH socket (which I assume ends up at VIN as well).

      I've read about different microcontrollers with the same situation, with some being able and some not being able to handle this scenario, I was wondering whether anyone has info/experience if this works with a LoPy.

      Cheers.

      L J robert-hhR 3 Replies Last reply Reply Quote 0
      • L Offline
        livius @Nunya Bidness
        last edited by

        @Nunya-Bidness
        I do not know it i understand you correctly.
        But LoPy do not recognize power source, than any should work.
        Only it must have enought power and voltage. If it is above 3.5V and lower then 5.5V and have 0.5 A in peak then i see no problem.

        think about people first, then computers

        1 Reply Last reply Reply Quote 0
        • J Offline
          jcaron @Nunya Bidness
          last edited by

          @Nunya-Bidness You will probably need to use a modified USB cable without power to avoid any issues.

          However, I suppose it's probably best if you have a common ground.

          1 Reply Last reply Reply Quote 1
          • robert-hhR Offline
            robert-hh @Nunya Bidness
            last edited by

            @Nunya-Bidness said in Powering through VIN while USB is connected at the same time:

            rather than the onboard PH socket (which I assume ends up at VIN as well).

            Actually not, since there is a charging circuitry and a power switch on board. The latter is located between VUSB and VBattery as inputs and VIN as output. Like @jcaron implied, it is not clear whether Vin and VUSB are decoupled. In any case you must avoid that the board is supplied through USB while the battery is connected to VIN. It would be charged with all power the USB port can supply, which may not be good and may overload the supply switch.

            1 Reply Last reply Reply Quote 0
            • G Offline
              Gijs
              last edited by

              Hi,
              I would not recommend powering through Vin with a battery and USB at the same time. As the 5V from the USB will start charging your battery connected on Vin. When connecting to the battery terminal, there is a detection circuit that switches the power source of Vin between USB and battery to not put 5V on the battery lines.

              1 Reply Last reply Reply Quote 1

              Hello! It looks like you're interested in this conversation, but you don't have an account yet.

              Getting fed up of having to scroll through the same posts each visit? When you register for an account, you'll always come back to exactly where you were before, and choose to be notified of new replies (either via email, or push notification). You'll also be able to save bookmarks and upvote posts to show your appreciation to other community members.

              With your input, this post could be even better 💗

              Register Login
              • 1 / 1
              • First post
                Last post

              Pycom on Twitter

              Pycom