USB A port on the MUF82AM usb-c-digital-av-multiport-adapter

• About the Apple USC-C Digital AV Multiport Adapter - Apple Support

https://support.apple.com/en-us/HT207806 published date: Aug 21, 2020

While I haven't discovered the Apple Specs page for this part number.

There are details pre-conditions of its use, & which ports supply power.

(More than one hardware-version of Adapter is covered by this article.)

"Because this adapter draws power from your Mac or iPad Pro even when

your Mac or iPad Pro is asleep, you might want to unplug it when it's

not also connected to power for charging." ~ use USB-C cable to charge.

"Use the USB-A port of this adapter with flash drives, cameras, and other

devices that connect to USB-A for data transfer or charging. It supports

USB 3 data-transfer speeds up to 5Gbps." ~ use AC power adapter

A USB-A port is allowed 5V and up to 1.5A as per the USB3.2 (Gen2) specifications (900mA for USB3.0). I've never performed any measurements on the adapter, but some of it will depend on the other devices connected to the adapter and even to the laptop.

I do know that the Apple multi-port adapter does not allow the full power of the charger to make it to the laptop when the charger is plugged into the multi-port adapter. I've personally experienced issues when using a charger with the multi-port adapter since some laptops will not even power on in this configuration (even when no other devices are connected to the adapter) yet work fine when the charger is connected directly to the laptop.