Psp on ps3?

I have a couple of psp games I've ripped and i've tried using psptops3 app to convert the isos to a remaster and/or mini.
I'm on rogero 4.46 and Every psp game I've converted and installed onto my ps3 just gives me a black screen and return to xmb menu.

Am I doing something wrong..? I know multiman has a retro section that has a psp option..
Are psp games playable on the ps3?