The Sky Blues confirmed their promotion back to the English top-flight last Friday and sealed the league title of the second tier with a 5-1 thrashing of Portsmouth at home on Tuesday.
The victory took Coventry to 89 points for the season and an unassailable lead with two games of the campaign still remaining.
Lampard had a trophy-laden career as a player at Chelsea but put this season's achievements high on his list of accomplishments.
"It's right at the top of my career," Lampard said. "I said it after Blackburn and to seal the title in the manner that we did, the way the team played from minute one, how we stepped it up in the second half.
"We've had a lot of these performances at the CBS [Arena] this year, this team has been so consistent.
"The last few weeks have been challenging in a way because of the pressure, because we're not used to this and we've got the results we needed recently to get us promoted.
"When you get this close, to go and do it with two games to spare is incredible, because this league gets harder.
"All the teams here give you different challenges in this league and these players have got 27 wins, it's amazing what they've done."
