USB-A charging brick voltages of 12V & 9V & 5.2V & 5.0V & 4.6V

[knuttle]

Are the multivoltage smarts in the phone or in the USB-A charging brick? In my wall wort box were a dozen USB charging bricks. Removing the duplicates, the varying voltages & current outputs were

4.6-5.3V@0.5A (duracell) 5.0V@.85A (doncdo) 5.1V@0.7A (lg) 5.1V@2.1A (newtrent rohs) 5.2V@2.4A (apple) 9.0V@1.8A & 5.0V@1.8A (lg) 9.0V@1.67A & 5.0V@2.0A (samsung) 12V@1.5A & 9V@2.0A & 5V@3.0A (motorola)

For the multivoltage bricks are they phone specific? Are they phone model specific?

Or can any recent phone use any of the multiple voltages? Especially the 12V and 9V multivoltage bricks.

Are the smarts in the phone to be able to use any multivoltage brick? Or in the brick?

[Dean Hoffman]

You might have better luck asking on sci.electronics.design

[trader_4]

IDK how you could be seeing 9V with USB-A. AFAIK, prior to USB-C voltage was set at 5V. The max current possible was increased over time, but not voltage, until C. The smarts to deal with the higher possible voltages came with USB-C and is in both ends. They communicate back and forth to identify what the device can accept, what the charger can deliver that's compliant.

[Mark Lloyd]

[snip]

My smartphone came with a power adapter that can output 9V through a USB-A connector. This is called QuickCharge. It is supposed to require negotiation to change the voltage.

[knuttle]

That was a mistake made when I was editing down the list to remove duplicates. This is the list posted to alt.electronics.repair as Dean suggested.

4.6-5.3V@0.5A (duracell) 5.0V@.85A (doncdo) 5.1V@0.7A (lg) 5.1V@2.1A (newtrent rohs) 5.2V@2.4A (apple) 9.0V@1.8A & 5.0V@1.8A (lg) 9.0V@1.67A & 5.0V@2.0A (samsung) 12V@1.5A & 9V@2.0A & 5V@3.0A (motorola)

Nobody seems to know how you can tell without already knowing.

[trader_4]

What connector is on the phone end? I bet it's USB-C. But you have a valid point. While the higher voltage charging didn't come around until USB-C, you can have a charger with USB-A output that supports the higher voltage, you use a cable that's USB-A on one end, USB-C on the other, so that explains what K was seeing.

[Mark Lloyd]

The cable is A to C. I have used a meter to verify 9V on the A connector.

I thought QuickCharge existed before USB-C.

[trader_4]

IDK, you could be right. And it's not just QuickCharge, which is the Qualcom standard. There is also USB Power delivery and then various manufacturer's eg Samsung, OnePlus did their own thing. OnePlus has some new phones that charge at 100W, not sure if they are being sold here. But they have other ones that are 35W, maybe 50W too. Then there are the mysteries. I have a one year old LG Velvet 5g, it's supposed to charge via USB at 25W, wirelessly at 15W. I've measured it and am only seeing 15W and 8W. I've tried a couple different chargers. Also saw some reviews where they were only seeing ~15W charging too.