Law enforcement sources at the San Francisco Police Department tell us their Special Victims Unit has obtained a warrant for Smith's arrest on charges stemming from a DV incident he allegedly fled from this weekend. The alleged victim is his fiancee.

Cops tell us the charges listed on the warrant include willful infliction of corporal injury (aka DV), assault with force likely to produce great bodily injury, false imprisonment and vandalism -- all of which are misdemeanors. We're also told police are working with his legal counsel to arrange a day and time for him to turn himself in and be processed.

As we reported ... Smith checked himself into rehab with the help of his fiancee's parents. She told us she was worried about him and was only focused on getting him well again.