USB 2.0 to USB C breakout for 900mA 2.0 device

I want to upgrade an old keyboard k65 rgb rapdifire which uses a USB 2.0 y cable to draw 900 mA of power.
I want to know if I can safely just connect the 5v gnd d+ and d- pins. And still draw 900ma through a USB c cable. Or do I need to change some resistor values somewhere.
So far I don’t even know where to look inside the USB spec for that.
Help is appreciated.

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Hi, DonPavlov.

If you want your device to be compliant with the USB specification, it would need to check that it is allowed to draw more than 500 mA before doing so. This StackExchange answer about using USB-C as a power source has a pretty good explanation of how it works. (Our board includes 5.1k pulldowns on the two CC pins, as described in step 2.)

Other than that, you should be fine just connecting the VBUS, GND, and data pins, and you shouldn’t need to change any resistors.


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I don’t charge Type C to C regularly, I had noticed this issue as well and I think it needs to be highlighted more as I suspect many OEMs are cheaping out on USB connectors assuming people mainly use Type C to Type A. The ESR seems to be the same basic shell and charging case as my Astrotec S60, but the S60 has balanced armature drivers and wireless charging.