Not quite.
Exchange rates in original/basic/expert D&D:
5cp=1sp, 5sp=1ep, 2ep=1gp, 5gp=1pp
Exchange rates in 1st Edition AD&D:
10cp=1sp, 10sp=1ep, 2ep=1gp, 5gp=1pp
Exchange rates in 2nd Edition AD&D:
10cp=1sp, 5sp=1ep, 2ep=1gp, 5gp=1pp
Exchange rates in 3rd Edition D&D:
10cp=1sp, 10sp=1gp, 10gp=1pp (the electrum piece seems to have evaporated)