Can i power a MIDI in/out circuit with the teensy alone?

Frukost

Well-known member
I am planning on building a teensy 4.0 midi circuit, and have been looking at the info at https://www.pjrc.com/teensy/td_libs_MIDI.html.

However, i wanted to ask about the power supply. In the schematics, it looks like an external 5V source is required to be connected to Vin and pin 8 on the opto ic (apparently the 3.x and the 4.x versions share the same schematics):

td_libs_MIDI_sch_t3.png

What's confusing me is that - judging by the photos of the finished circuit - the power supply seems to come from the teensy alone.

I'm asking because - ideally - i'd like to build the circuit in a fashion that allows tapping power from the teensy alone. It would be nice to have the sole USB connection power everything.

Could someone please clarify? Thanks in advance!
 
Yes, USB power is fine.

When Teensy is powered by the USB cable, and if you haven't cut the VUSB-VIN pads apart on the bottom side, then the USB power will appear at the VIN pin. It is easily capable of powering the 6N138 or similar optocouplers.
 
Back
Top