Micro USB Voltage Isolator

thingiverse

This is a simple case to hold a micro USB breakout board and a male micro USB plug for purposes of isolating the motherboard in a USB printer from the USB supplied 5v power. The CR6 motherboards appear to have an issue with the printer motherboard trying to draw too much power from the USB connected to your computer or octopi when the printer is powered down, leading to burned USB ports and electronics. I understand other printer motherboards may suffer from the same issue, but the ones that I know of are the CR6 boards. There's a couple of solutions available, including taping the 5v pin on the supply side, hacking a usb cable to cut the voltage line, and a couple of commercially available power isolation devices. I had the board and plug sitting around in my miscellaneous projects part, so I drew up a quick case, printed it and soldered it. I'm sharing it here in case it might be helpful to someone else. The micro usb breakout board I used is this one: https://smile.amazon.com/gp/product/B07KS1RPMP/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 You can use pretty much any male micro usb plug though I used is this one: https://smile.amazon.com/gp/product/B00AQWUCAA/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 Note: Unless you need multiple isolators or have other uses for the boards and plugs, it probably doesn't make economic sense to order the parts for this, as the commercially available solutions will run a couple bucks less than the cost for the multipacks that I linked. The lid is a snap fit, though it is probably smart to use a couple drops of superglue to hold it together. It's also helpful to use a touch of hot glue on the male plug side after everything is inserted to hold the plug in place. The Fusion 360 file is included in case you need to make modifications. Be careful soldering the male plug side - the pads are tiny and it's easy to get solder flowing across them. You also have to be VERY fast or you risk melting the plug. Use one of the many pinout diagrams that are available to match the plug pins to the board pads.