Financial terms were not announced Thursday.
The 6-foot-2, 198-pound Tillman spent his previous 12 seasons in the league with the Chicago Bears, where he was selected to the Pro Bowl in 2011 and 2012. He has started 152 games during his career, but triceps injuries have limited him to 10 games the past two seasons.
Tillman, 34, previously played under Panthers coach Ron Rivera and assistant head coach/secondary Steve Wilks in Chicago.
Tillman leads active defensive backs with 41 forced fumbles and is fourth in interceptions (36) and second with interception returns for touchdowns (eight).
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