How do you charge your iPad while being tethered?


I usually charge my iPad pro with the29W usb c and usb c to lightning cable.
But when I use astropad studio on the other hand I have to plug into my mac mini with regular usb. This drains my iPad battery a lot. … Do you have any tips for charging while being plugged in? Is there a lighting splitter for charging and conecting to mac at the same time?