Campbell gives the Packers another option in the middle of their defense, where they released veteran Christian Kirksey earlier this offseason.
Packers coach Matt LaFleur was on the Falcons' coaching staff during Campbell's rookie year of 2016.
Campbell, a fourth-round pick of the Falcons in 2016, has started 70 of his 75 career games, including all 16 games last season for the Cardinals. Previously, he spent four years in Atlanta, where he started 54 of 59 career games. He has 462 career tackles in five seasons, including a career-high 129 in 2019. He played last season on a one-year, $6 million contract with the Cardinals.