The 76ers signed the former first-round pick on Tuesday. Carney spent last season with the Minnesota Timberwolves, averaging 7.2 points and 1.9 rebounds in 67 games, including six starts.
The 76ers acquired Carney in a draft-night trade in 2006 after he was selected 16th overall by Chicago. After two seasons with the Sixers, Philadelphia traded him to Minnesota along with Calvin Booth in July 2008.
General manager Ed Stefanski says Carney's athleticism will fit the up-tempo style favored by new coach Eddie Jordan.