Apple usb-c to HDMI & USB-c adapter does not charge attached iPad when a usb-c charging cable is plugged into the usb-c port on the adapter. The picture on the box implies this will work.
iPad Pro, iPadOS 18
When using a USB Type-A power source, charging power is limited to 12W (i.e. 2.4A @5V).
While an iPad requires at least 12W to reliably charge, as the connected adapter itself requires power from the Power Adapter to run its own electronics, this additional load leaves insufficient power to charge the iPad.
By contrast, when using a USB-C Power Adapter of 20W or greater, the connected Adapter's power needs are met while also meeting the iPad's minimum power requirement to charge its battery.
When using a USB Type-A power source, charging power is limited to 12W (i.e. 2.4A @5V).
While an iPad requires at least 12W to reliably charge, as the connected adapter itself requires power from the Power Adapter to run its own electronics, this additional load leaves insufficient power to charge the iPad.
By contrast, when using a USB-C Power Adapter of 20W or greater, the connected Adapter's power needs are met while also meeting the iPad's minimum power requirement to charge its battery.
Your iPad is designed to be charged from a USB-C Power Adapter that supports USB PD. While it is possible to charge an iPad, albeit slowly, using a USB Type-A power source, this is inadequate to charge your iPad while also connecting USB accessories.
With the exception of iPads purchased within the UK and EU countries, where Power Adapters are no longer supplied with a new iPad, in most countries iPads are now supplied with an Apple USB-C 20W Power Adapter.
Using an appropriate USB-C Power Adapter rated at 20W will optimally charge your iPad. Using a USB-C Power Adapter with a higher power output will not significantly improve the maximum charging rate of the iPad - but does provide additional power-budget to supply adequate power to other connected devices while maintaining adequate power to charge the iPad.
Just found out adapter does work if you use a usb-c to usb-c charging cable; but does not work (ie charge the attached iPad) if you use a USB-A to usb-c charging cable, with USB-A plugged into power adapter and USB-c cable plugged into usb-c port of the digital AV multiport adapter. This is not clear in any documentation. HTH
So I was using an original iPad 12W power adapter with a USB-A output socket, which did not manage to charge the iPad, the iPad showed no signs it was getting any power. Whereas switching to the USB-C power adapter which came with the iPad worked as advertised. I also tried a Belkin battery pack with USB-A connector, which I thought put out a reasonable power level, but this also didn’t work, though the adapter did get warm. I thought the iPad would charge at any power level, unless the voltage was too low. Does this mean I should switch to USB-C power adapters as soon as possible?
Apple usb-c to HDMI & USB-c adapter does not charge attached iPad
