ChefArtorias t1_itmwo88 wrote on October 24, 2022 at 8:35 PM

Reply to comment by HerbHurtHoover in USB-C iPhone will be mandatory in Europe as EU law passes final stage by prehistoric_knight

Sometimes I know that is the case, like I wouldn't expect a cheap charger to power the switch/deck very quickly, especially not while playing. The powerful chargers not working on less powerful devices is what confuses me. Maybe there's a system in place to prevent it like more wattage from the charger would be dangerous to the small device. Steam charger is brand new and won't charge my headphones which baffles me but I am pretty ignorant about the details of how electricity works.

VIKTORVAV99 t1_itmxpl5 wrote on October 24, 2022 at 8:42 PM

It has nothing to do with how electricity works and everything to do with the negotiation between the charger, cord and device. They all contain microchips that contains the supported wattage and amperage and they will select the highest supported wattage and amperage by all parts of the chain.

ChefArtorias t1_itn6524 wrote on October 24, 2022 at 9:38 PM

While I get what you're saying both of those are different aspects of electricity which the microchips are there to regulate. I do know some about electric systems from doing construction but not really details of electronics.

happyscrappy t1_itqyatl wrote on October 25, 2022 at 5:33 PM

A charger capable of 5A and 20V is the "most powerful" charger. But some devices don't work at 20V.

A charger must be able to supply 5V, and may be able to supply 9V, 15V or 20V. It might supply all 4, or some subset. All devices must support 5V and may support other voltages. So if someone makes a charger that does 5V and 20V and then you plug in a device that wants either 5V or 9V then they will agree on 5V. Then that means you can't charge faster than 15W.

According to the spec it should still charge, just charge slowly. But some companies interpret the spec rather liberally or just don't comply. And then it may not charge at all.

Honestly, Valve seems to do a rather poor job with USB C (USB-PD) really support. So their charger is probably poor at it. A good quality USB C charger may support both your headphones and Steam deck. In case you care, like if you wanted to take only one charger on a trip. Better test it first before you leave on the trip of course!