Posted this in General Discussion, but I realize it makes more sense here:
I'm making a custom PCB for my neuroscience lab to record and generate different signals during experimentation. We're currently using the Teensy 3.5 for the 5V tolerant input pins and 2 DAC outs for true analog outputs.
With our PCB, I wanted to have multiple possible power inputs, as USB alone from a hub often does not yield enought current (~250mA needed). I'm aware of powered USB hubs but I wanted a direct option if that is unavailable. I used diodes to handle the different input voltages. We also take in signals and voltage from a rotary encoder, and have several analog and digital I/O through BNC. The PCB will end up in a metal enclosure roughly 110mm x 80 mm, with height 30 mm.
My schematic is not too different from the 3.5 schematic, just with those added features.
My main questions are how to add capacitors and a ground plane to the crystals, and whether my diode OR-ing logic makes sense.
Any feedback or suggestions are greatly appreciated. This is my first PCB design, and I'm using EAGLE.
https://drive.google.com/file/d/1qg2tsyXz-LSmPaRAfYKTHLkp4VpMtHJ8/view?usp=sharing
I'm making a custom PCB for my neuroscience lab to record and generate different signals during experimentation. We're currently using the Teensy 3.5 for the 5V tolerant input pins and 2 DAC outs for true analog outputs.
With our PCB, I wanted to have multiple possible power inputs, as USB alone from a hub often does not yield enought current (~250mA needed). I'm aware of powered USB hubs but I wanted a direct option if that is unavailable. I used diodes to handle the different input voltages. We also take in signals and voltage from a rotary encoder, and have several analog and digital I/O through BNC. The PCB will end up in a metal enclosure roughly 110mm x 80 mm, with height 30 mm.
My schematic is not too different from the 3.5 schematic, just with those added features.
My main questions are how to add capacitors and a ground plane to the crystals, and whether my diode OR-ing logic makes sense.
Any feedback or suggestions are greatly appreciated. This is my first PCB design, and I'm using EAGLE.
https://drive.google.com/file/d/1qg2tsyXz-LSmPaRAfYKTHLkp4VpMtHJ8/view?usp=sharing
