The Portuguese, who will contest the charge, was sent to the stands for encroaching on the turf and approaching the match referee at the end of the match on March 15. (Agencies)
Mourinho had been angered after Foy showed Chelsea's Brazilian midfielder Ramires a straight red card for a stamp on Villa's Moroccan international Karim El Ahmadi.
The manager said after the match that Foy, who also sent off Brazilian Willian, should not be allowed to take charge of any more Chelsea matches.
On Friday, Mourinho fanned the flames by stating he could "never accept" Foy's performance.
"What happened in the defeat against Aston Villa I never accept," he told reporters.
"I have a lot of experience in football and I learn a lot of things, and one of the things I learn is that you can win and you can lose and if you lose in the right way you have to move on, try not to lose again and try to learn from the mistakes, but I never learn from and I never accept losing that way.
"I accept and learn how to lose because of the bad performance or because the opponent was better. I learn to lose when the referee makes a mistake because we can also lose with my mistake. I learn everything.
"The only thing I didn't learn is to lose with that kind of refereeing performance because it is not a mistake, it is a performance."
Mourinho hinted that Foy was solely to blame for the defeat at Villa Park.
"Other matches we lost because we didn't play well, because the opponent played much better than us. Against Stoke we had chances to kill the game and we didn't. Against Newcastle in the second half they played much better than us," he said.
The Portuguese, who will contest the charge, was sent to the stands for encroaching on the turf and approaching the match referee at the end of the match on March 15.