The 25-year-old, who is the son of former England international Teddy, has spent the last two seasons at Bournemouth.
Dons boss Neal Ardley said: "Charlie has scored a lot of goals at a lower level and I feel that he deserves a chance to prove that he can score goals in the Football League.
"I think he can certainly do that and he will do very well for us. He also scored when he moved to Bournemouth, but a bad foot injury put him out for a while. Bournemouth obviously saw something in him, but they got promoted to the Championship and are moving in a different direction.
"Charlie is technically very good, he is tall and similar in stature to Jack Midson. I believe that in Jack and Charlie we have two players who know where to be in the box and how to score goals.
"Charlie can also drop deeper and link the play. If we do want to try and get the ball down a bit more and link-up the play in forward areas then Charlie will fit into that."