Forum Rule: Always post complete source code & details to reproduce any issue!
Results 1 to 6 of 6

Thread: Eurorack Teensy Power

  1. #1

    Eurorack Teensy Power

    Hi Guys,

    I was wondering how one would power / generate the +12v, -12v, 5v requirements for a eurorack system with the Teensy series? Is there a version of Teensy that is more suited to this, ie 3.6 vs 3.2 or is it generally the same?

    I don't have any experience with power regulators etc, so any advice or direction would be great

    Not even sure where to start to be honest.

    Thanks
    M
    Last edited by mtiger; 03-23-2018 at 07:22 PM.

  2. #2
    Senior Member PaulStoffregen's Avatar
    Join Date
    Nov 2012
    Posts
    22,238
    Normally you would buy a power supply. They're made out of very specialized parts that aren't anything like a Teensy or any other microcontroller board. A board like Teensy might be useful as some sort of monitoring device (to alert you if the power supply is getting too hot or otherwise not working well), but it generally isn't very useful to actually make the power supply itself.

    If the input will be AC mains (120V in US, 240V in most of the world), building your own power supply from scratch is not recommended. There are many important safety issues to consider in the design of these power supplies using AC mains voltage, where mistakes could lead to a build that appears to work fine but later could start a fire or electrocute you or someone you know. Not a beginner-level project!

    Fortunately power supplies are very common and pretty inexpensive.

  3. #3
    Hi Paul,

    Thanks for your response. Obviously due to my misunderstanding of this area of electronics, what i mean't was 'how would the Teensy deal with the incoming +12v, -12v, 5v power output that most busboards have for the eurorack system. Not actually creating a power supply for this format.

    If i am trying to create a module, for example, that simply generates different voltages and spits them out of a CV jack to carry the signal to another eurorack module, how do i know what power is required, if its from either the positive, negative or 5v. Super noob on this topic.

    How would i power a teensy from this spec? Assuming its voltage regulators to bring the voltage down to the 5v for the Teensy? However, what if i need more voltage as some require / have a higher tolerance from say 0 - 10v.

    A little lost here as where to look, what to research etc? Appreciate your help

  4. #4
    Junior Member blittled's Avatar
    Join Date
    Sep 2017
    Location
    Northwestern PA
    Posts
    11
    You can use the 5V power output to externally power a Teensy as mentioned in https://www.pjrc.com/teensy/external_power.html. If you want to connect the I/O pins of a Teensy to lines that use 5V you should use a 5 Volt tolerant Teensy such as the Teensy 3.5.

  5. #5
    Senior Member PaulStoffregen's Avatar
    Join Date
    Nov 2012
    Posts
    22,238
    Quote Originally Posted by mtiger View Post
    If i am trying to create a module, for example, that simply generates different voltages and spits them out of a CV jack to carry the signal to another eurorack module, how do i know what power is required, if its from either the positive, negative or 5v. Super noob on this topic.
    This the most important part, context to understand your question! Everyone starts as a beginner. But if you ask only a narrow tech question, at best we can only give you the specific answer. With an understanding of what you're really trying to accomplish, we can actually help.

    In this case, you'll probably power the Teensy from 5V. Teensy LC & 3.x run on 3.3V power, but they have a VIN pin for 5V and then they create 3.3V.

    To create a CV output, you can use either Teensy's DAC pin or you can add a fancy DAC chip which has better performance than Teensy's built in DAC. Probably the best example of the fancy DAC route is the Ornament and Crime module, which is fully open source. It's complex, but that's a good place to look for a well designed solution to generate the best quality CV output.

    For a cheaper approach using the built in DAC pin, which gives either 0 to 3.3V or 0 to 1.2V (with lower noise and better stability), you'd add an opamp circuit to boost Teensy's lower voltage DAC signal to the higher voltage used for CV. I'm not a eurorack expert, but my understanding is at least a few different ranges like -5V to +5V, 0 to +5V, and 0 to +8V are used for CV, so the very first step would be to figure out exactly which of those you need.

    There are lots of other forums more specific to DIY eurorack projects, though not so specific for Teensy. Whereever you post, remember we can help you much more if you put some extra effort into your question to give us understanding & context of what you're really trying to accomplish. Narrow tech questions are easy, but unless you're an expert (and maybe not even then) it's very difficult to know exactly what to ask. Best to explain your goals.

  6. #6
    Thanks guys, appreciate your guidance.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •