I have been trying to find a device with a MPU core and a USB 2.0 interface. Prefer if the MPU is 8051 but it doesn't matter. Must be low power with suspend currents under 30uA. I have seen the Cypress units and they are almost perfect but the wake-up time is ~5ms. My current design is up and running in around 120us after wake up. It is a data logger so it wakes up as fast as every 10ms and spends around 50us collecting data,
Currently I provide the NAND flash translation layer in the firmware on the device. I am pursuing this solution so that I may have the USB mass storage capability making data upload easier.
Elan.