iPad mini Why won't iPad Mini 6 charge with 20 watt charger but iPhone 13 ProMax does with same charger?

[RetiredInFl]

Very weird. I have a USB HUB with a 20watt USB C charging port. My iPad MINI 6 will not charge from that port but my iPhone 13 Pro Max will. The Mini 6 will also charge (albeit slowly) with a very old OLD APPLE iPhone 6 wall charger which is only 5 watts (using a USB A->USB C adapter. The Mini 6 also charges fine with another USB C charger. Tried 3 different Apple OEM cables.

 

[ApfelKuchen]

Hmmm. I have a notion, but nothing solid.

Afaik, Apple supplies only USB-C PD (Power Delivery) rated cables. But what do we know about that USB hub? The USB-C PD standard has been through a number of revisions (it's currently at version 3.1) - if it's an older hub, it's at least conceivable there's a difference between the manufacturer's implementation and recent standards. Say, for example, that the manufacturer used a preliminary implementation that did not find its way to the adopted USB-C PD standard (I have a recollection that some manufacturers interested in being early-to-market did this sort of thing). The chip inside the cable that governs how it will connect to the equipment (such as the voltages delivered via the power pins/wires) can be programmed to reject non-standard voltages/currents/implementations.

It's also possible that the chip in Apple's USB-C to USB-C cables is not the same as the chip in the Lightning to USB-C cable you've been using - hypothetically, one chip could be more "forgiving" of certain USB-C implementations than the other. (This is one of the things I dislike about USB-C - multiple standards/multiple optional implementations... having the same connector does not mean 100% compatibility with every device that mates with that connector.)

So, I'd suggest a visit to the hub manufacturers website to see if there are others encountering the same issue.

 

[Zazoh]

It also charges on the 30watt charger for the MacBook Air (M1)

The ideas presented by @ApfelKuchen are likely it.

 

[TheIntruder]

All spec compliant C-to-C cables support PD, at a minimum of 60W.

There is no such thing as a non-PD rated cable, but it wouldn't have surprised me if someone inside the USB IF considered that scenario and thought, "Good idea, but nah, maybe we're confusing people enough already with the number of cables we've already got, and the brilliant nomenclature scheme the interns have concocted. In fact, we've got even more labels that the manufacturers won't apply to their products in the pipeline!"

Some sort of incompatibility, or implementation issue is a real possibility, but I'd give the benefit of the doubt to Apple, versus the maker of the unnamed hub.