USB Host device powered by Teensy 3.6 host port or power rails.. which is advisable?

Status
Not open for further replies.
My project is being fed with 5V and 12V power ( eurorack module). I also have 3.3 volt regulator powering a few bits and blocks to ensure teensy doesn't see more that 3V on its pins. the Teensy 3.6 itself is being powered by the 5V rail on it's VIN pin.

I already have a lot going on with the module and I was wondering if it was advisable to power the midi keyboard (connecting to teensy as a host) via the 5 volt rail instead of the onboard teensy host port 5V pin.
I have tried it and it seems to work fine. I haven't seen anything abnormal so far while teensy is still only receiving inputs on the DP & DM pins while the other 3 pins (5V, GND, GND) have been left unused.

Thoughts or cautions??!

Thanks in advance.
 
Last edited:
@PaulStoffregen and others are better at answering some of the electronics stuff better than I am...
But I think either should work.

If you look at the schematic of T3.6 in the section: https://www.pjrc.com/store/teensy36.html#tech
You will see the VUSB or VIN more or less goes directly to the USB Host through TPD... chip which is there to help with USB power management. In particular to help when you hot plug in a device into the USB host connection, that the startup power request for the device does not cause the USB connection to the PC does not request too much power...
 
Hey, Thanks KurtE, that makes sense. I will test a bit further and post anything I notice worth mentioning that could help somebody else. Cheers!
 
Status
Not open for further replies.
Back
Top