wjlo050912_06_X17crop230.jpgJennifer Lopez has filed a $20 million lawsuit against her former driver Hakob Manoukian ... claiming he tried to blackmail her by threatening to leak private information that he overheard while chauffeuring the singer around.

According to the suit, Lopez worked as JLo's driver for close to a month before quitting after an argument with her management team. The papers go on to say that in October 2011, he took part in "blackmail, extortion, and related acts."

The lawsuit says Manoukian was "forced to resign" from his job after he was denied "production pay."

On October 3, 2011, Manoukian's former attorney reportedly "made written and oral demands that unless Manoukian was paid $2.8M, he would disclose sensitive and personal information that he had allegedly heard while driving Ms. Lopez."

Lopez's attorney claims that this was "in total disregard of Manoukian's signed confidentiality agreement."