SIX-foot-four-inch Dunn penned a three-year contract with the Sky Blues in July 2011 from former club Northampton Town.
The 24-year-old was out of contract with the Cobblers who received an undisclosed compensation fee because of his age.
Dunn had made more than 100 League appearances prior to his move to the Ricoh Arena after joining Northampton Town as a scholar after moving from the MK Don's academy