There are flash drive data recovery tools on the web. If the drive has failed physically, then you are out of luck. Always keep multiple backups of valuable data. DvDs are cheap.
Greg, there is no schematic for a flash jump drive. as kchristie stated if it's failed it's done there is nothing you can do unless you want to pay thousands of dollars to send it to a lab to take it apart and see if they can extra any information from the drive directly.
Just a crazy suggestion... what about purchasing another drive of the same type and swapping the chip that stores the data, then see if you can read it??
Do you know why the jump drive stopped working, eg: did you leave it in a pocket and run it through a washing machine?
I have done this with jump drives, they usually survive, but some times not. I have revived a dead one once by opening it up and leaving it to dry by power supply vent, then cleaning any little spots of corrosion on the circuit board with a Q-tip and WD-40. I have also recovered a cell phone this way.