Powering Striso when connected to Android tablet

Hi,

probably not exactly a Striso question but I took my board on vacation and use it as Midi input for a few Android apps. I’m connecting to my phone (Huawei Media Tab) via usb, that works well, but if I do so the phone battery also needs to power the board. Is there a clever way (maybe via a Hub of some sort) of using an external USB charger with the board and connect to the phone at the same time? Or do phones have the ability to split their usb input somehow? Don’t know enough about USB powering of devices, so maybe here has some prior art to share?

Cheers

There are plenty of powered USB hubs, but these all seem to use a wall-wart for power, so they aren’t useful for portable/off-grid use. I think there are splitters that provide for supplementary power via USB, which is what you’d need to glue together a power bank with a hub. I’m surprised that combined powerbank/usb hub isn’t a thing.

There is a clever way:

  • Use a product such as the CME WIDI Uhost, then connect USB OTG cables from it to the Striso, while also connecting a USB cable from the CME WIDI Uhost to a power bank. This will power the Striso through the CME WIDI Uhost, as it supplies 500mA, which is more than enough for the Striso’s requirement of 150mA.
  • From here, you have two options:
    • Use your Android device’s native Bluetooth to connect to the CME WIDI Uhost. No additional setup required.
    • Get another CME WIDI Uhost for your Android device, then connect them using a USB OTG cable to power the CME WIDI Uhost and bypass your Android’s native Bluetooth, lowering the latency between both CME WIDI devices down to 3 ms.

Just remember to update the firmware on the CME WIDI products before using them.

I just tried with a USB-C docking station (this one), and that works fluently. It has a USB-A port where the Striso can be plugged in and a USB-C charging only port that can be powered (also from a power bank). This does charge the phone as well.

I’m not sure if hubs without Power Delivery Pass-Through also charge the phone, but they should at least power the Striso board.

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