The 31-year-old will remain with the Iron until their home game with Shrewsbury Town and goes straight into the squad for the home game with Notts County in League One on Saturday.
The powerful Bradford-born forward initially joined the Tractor Boys in June 2011 but has only made 19 appearances since joining.
Ellington is best known for forming a lethal partnership with Jason Roberts, scoring 67 goals in 146 games as he fired Wigan into the Premier League, before going on to have spells with West Brom, Watford and Preston amongst others.
The former Bristol Rovers man has scored 147 goals in 491 appearances.