"That's So Raven" actor Orlando Brown was so drunk at the time of his DUI arrest last month, his blood alcohol level was more than TWICE the legal limit ... law enforcement sources tell TMZ.
We're told Brown's B.A.C. was measured at .17 during the August 12 arrest -- more than double the limit in California, which is .08.
23-year-old Brown has been charged with 2 counts of DUI and could spend several months in jail if convicted.
TMZ broke the story, Brown was originally pulled over for driving without a license plate just a short distance from his L.A. home -- when cops noticed the smell of alcohol and arrested him.
He's due back in court later this month.