Re: Recognizing PD QC chargers

Arno Welzel <usenet@arnowelzel.de> wrote:

... does NOT USE USB-PD of course ...
 
Because then it ALWAYS works with a USB-A connector, maybe just with the
minimum charge at 5V and 0.5A. But USB-C requires to negotiate the
charging protocol before you can draw power to charge.

I'm guessing the USB-C input on the speaker doesn't have the appropriate
CC1/CC2 resistors to tell the charger to output 5V at some amps.  So the PSU
is only doing the minimum output according to the spec.  On the USB-A output
from the charger it'll output 5V all the time, even with nothing plugged in,
but on USB-C you have to ask for it.  Maybe they just swapped a microUSB for
a USB-C socket without any further adjustments.

A dumb PSU will output 5V regardless, but this one is too smart.

How to add the resistors:
https://forum.digikey.com/t/simple-way-to-use-usb-type-c-to-get-5v-at-up-to-3a-15w/7016

A simpler alternative would be a USB-C to USB-A female cable, followed by a
USB-A male to C cable.  The C to A female cable should have the resistors in
place to force the output to 5V.

Theo