USB-C PD power injector to use with standard USB2.0 cable - Page 1
Forum section: electronics / projects

author: AloyseTech
author_rank: Regular Contributor
timestamp: September 12, 2018, 10:04:01 am
content: Hi,I have a space constrained application where only one plug to the outside world is possible. I need USB communication (2.0 High Speed) and >20W power supply. With a USB-C PD host, there is no issue if the host is able to provide the 20W+ requirements. But this product should also be usable using "old" laptops or computer having only USB 2.0 standard connectivity. Since the USB plug is shared between Power and Data, I need some kind of injector/splitter (see attached functional diagram). Do you guys know any existing product that does this? I would really like to avoid design and produce a custom adapter myself.If you have other solution (single connector 20W power and USB data), I would be happy to know as well.Thanks in advance for your help

author: krho
author_rank: Regular Contributor
timestamp: September 12, 2018, 03:12:31 pm
content: I would go with usb-c and provide usb-c to micro usb adapter for those who don't have the usb-c port on computer.Unless you need both at the same time.

author: AloyseTech
author_rank: Regular Contributor
timestamp: September 12, 2018, 03:14:29 pm
content: I need both power and data communication at the same time. Using a plain USB-C to USB-A cable is not an option...

author: krho
author_rank: Regular Contributor
timestamp: September 12, 2018, 03:50:40 pm
content: I haven't seen anything like that hover if you do have USB-PD capable power supply then I'd do muxing myself. It could be a passive thing.Where you mux the PD capable power supply and route pins DATA pins from micro usb connector to USB-C one that goes to the device.

author: AloyseTech
author_rank: Regular Contributor
timestamp: September 12, 2018, 04:26:10 pm
content: Maybe there is existing product that does that already? I mean designing it is not that hard, but it add costs and production requirements. The goal would be to be able to focus only on the device itself and find a way to power it with existing solutions

author: AloyseTech
author_rank: Regular Contributor
timestamp: September 12, 2018, 04:49:19 pm
content: Quote from: blueskull on September 12, 2018, 04:33:43 pmYes but again, if the product already exists, it would be easier and cheaper to redirect any customer needing standard USB to this product.

author: LapTop006
author_rank: Unknown
timestamp: September 13, 2018, 03:57:45 am
content: Theoreticallythis TI reference designcan do it by just reflashing firmware, although when I had someone try that they weren't successful in getting that working (also looks like it's now much more expensive than it was, making this a far less sensible option).Many of the PD sink designs out there could fairly easily be modified for this too.

author: timg11
author_rank: Contributor
timestamp: August 26, 2023, 08:23:04 pm
content: @AloyseTech,I was searching for the same thing - a simple "power injector" for allowing a USB-C device with higher than standard USB2.0 power requirements but only using USB2 data to plug into a USB A port and provide power from an external supply.Did you ever find a solution?