Amanda Bynes has officially been charged with DUI after her arrest back in April -- when she sideswiped a cop car and allegedly attempted to flee the scene.
Bynes has been charged with one count of misdemeanor DUI -- and the D.A. has sought a sentencing enhancement because the actress refused to take either a breathalyzer or a blood test.
Bynes has not been charged with hit-and-run.
If convicted -- with the sentencing enhancement -- we're told Bynes faces a minimum of 48 hours in jail ... and a maximum of 6 months.
But because of jail overcrowding, it's unlikely Bynes will ever serve longer than a few hours.
4:35 PM PT -- And now this ... Amanda just tweeted, "Hey @BarackObama... I don't drink. Please fire the cop who arrested me. I also don't hit and run. The end."