I’m working on a small project (and if successful, I will write up instructions and post 3D printed part STLs because I’m designing a modified case/enclosure as well!) - I’ve connected a small audio amp board (an LQ-AMP10W) and 2x5W 4Ω speakers to the following pins on VPE:
(Side note: It’s a shame that there isn’t one header with both 5V and GND! Or did I miss it?)
I’m monitoring the total power draw of VPE with the amp connected with an AVHzY.
When not playing music: ~4.8V @ ~0.1A
When playing music: ~4.2–4.6V @ ~0.2–0.4A
Absolute maximum amp draw observed (100% volume on VPE and amp, with a loud song): ~0.6A
My question is: Is this harmful long-term to the VPE mainboard? What is the minimum and maximum voltage input for the board (or, how much voltage drop can it handle before bad stuff starts to happen?), and how much current (in amps) can the 5V pin provide? (Let’s assume that we’ve connected the USB-C port to a robust, clean power supply that can reliably deliver up to 5V @ 2.4A.)
(Note: You may ask “Why didn’t you use the Grove port?” - In the schematics for VPE, the Grove port can only deliver a maximum of 200mA, not nearly enough to drive 5W speakers.)
Yeah missed that. If you’re building the case the best place to draw is where power hits the bus. What about putting in your own regulator and feeding the vpe’s usb power in from yours. Then power isn’t your issue
I thought about that, but I don’t have enough experience to muck around with USB-C power. I wanted as simple a solution as possible, and letting the VPE board handle the power is as simple as it gets
I thought about using a USB-C splitter which may work as well, but then I would have to modify the 3D printed enclosure to contain a separate place to mount the USB-C female input (right now I just have a small hole that allows access to the USB-C port directly on the VPE board).
Is there a cheap electronic component you have in mind that would achieve what you’re suggesting?
From what I can tell, the USB-C 5V goes through a Current limiter (which also protects against in-rush currents) and limits the current to around 2.0A to supply +5V to the main board which you have tapped into.
If all your are seeing is 0.6A draw max, I don’t think there will be a problem. But on the otherhand, if the AMP happened to pull closer to 1A (5W) while the VAPE is surging current trying to do some other kind of heavy duty processing, then it ?may? cause the VAPE to drop out?
