"I'm just eager, eager to get in," Dansby told reporters.
"These guys are hungry. That inspires me to come in and join on board. Let's go, I'm ready."
The five-year contract will pay Dansby $43 million, including a guaranteed $22 million, to make him the NFL's highest-paid inside linebacker.
Dansby was a second-round pick for the Cardinals in the 2004 NFL draft. He recorded 563 tackles, 25- sacks and 10 interceptions in 90 games with Arizona.
(Reporting by Mike Mouat in Windsor, Ontario)