The 29-year-old, a former 100m world record holder who has clocked 9.85 this season, is a medal contender, even if he is firmly number three on the Jamaican team.
Powell has been overshadowed by Usain Bolt and Yohan Blake.
Having missed out on individual medals at the last two Olympics, finishing fifth in Athens 2004 and Beijing 2008, says he is determined to bid goodbye to the Games on a high in London.
'I'm pumped up for these Games,' he said.
'I'm not getting any younger. It's probably my last one.
'Everyone is excited. Jamaica is excited, all the athletes. There's a lot of attention on Jamaica right now and everyone is pushing for the Olympics'.