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hcls
Associate II
March 27, 2019
Question

USB-C with STUSB4500 - get power from laptop

  • March 27, 2019
  • 2 replies
  • 684 views

Hello :)

This USB-C is confusing me. According the standard you should be able to receive or to send power. I am using the STEVAL-ISC005V1 Eval board form ST. Unfortunately the PD2 and the PD3 line is not active if I plug the device into a Laptop.

So my question: How to configure Windows to act as a power source?

A short google search showed always results about on how to load your laptop with the USB-C port but not on how to act as a 20V power source.

Is it possible to get 100 Watts out of a USB-C plug from a Laptop?

Thanks for you answers.

Cheers,

Chris

    This topic has been closed for replies.

    2 replies

    ST Employee
    March 27, 2019

    ​Hello Chris,

    USB-C standard allows indeed to implement many features, but not all are mandatory (because it is not useful for some application, or because it would cost too much). Latest laptops I have seen can be powered directly from 20V power source, and on the same port, are able to provide 5V. But 100W is definitely too much for a portable device whose battery is not big enough (except maybe dedicated and high ends power banks). Some high end smartphones are able to source 9V.

    rgds,

    Benoit

    hcls
    hclsAuthor
    Associate II
    March 28, 2019

    Hi Benoit

    Thanks for your reply.

    Well that's also what I think, most manufacturers just implement a little part of the whole standard :). In my eyes it would make a lot of sense to power a device, let's say a printer, from your laptop if you just want to print one paper. Therefore you could save the power cable of the printer.

    Anyhow, Windows does not support this at all as far as I understood. Else I would need to choose if I plug in my phone on the laptop whether I want to send (charge the phone) or receive (charge the laptop) energy.

    Is it possible to find out if the laptop is supporting to act as a USB-C PD Source? I mean if the laptop specifies USB-C 3.2 compliance seams not to be enough.

    Regards

    Chris