As I have already written in another thread here. If you want to charge as fast as possible you need a brick that supports Power Delivery with 15V, because the new iPad Pros can handle max 45W (15V/3A) in theory. In practice it‘s less then 40W.
Apple offers several Power Adapter for this:
- Apple 30W USB-C Power Adapter 30W (20V/1,5 A PD), 30W (15V/2A PD), 15W (5,V/3A) / this one replaced the 29W brick which supports (14,5V/2A PD) 12,48W (5,2V/2,4A)
- Apple 61W USB-C Power Adapter A1947 (13” MacBook Pro 2018) 60,3W (20,3V/3A PD), 45W (15V/3A PD), 27W (9V/3A PD), 15,6W (5,2V/3A)
The following two adapters are not supporting 15V. So, they should charge slower than the ‘15V Adapters’. But the new iPad Pro should also take advantage of the 9V/3A from this two adapters and also charge faster than the original 18W iPad power brick:
- Apple 61W USB-C Power Adapter A1718 60,3W (20,3V/3A PD), 27W (9V/3A PD), 12,48W (5,2V/2,4A)
- Apple 87W USB-C Power Adapter 86,86W (20,2V/4,3A PD), 27W (9V/3A PD), 12,48W (5,2V/2,4A)