Posted on May 17, 2011 at 14:27Yes this will work, you need to review the clock trees in the reference manual.
The USBCLK = PLLCLK/1 or PLLCLK/1.5, permitting a 48 MHz or 72 MHz SYSCLK for USB operation. You could also technically run the CPU at 8 or 16 MHz, and have the PLL just run the USB. The AHB, APBx can be a fraction of the SYSCLK.
The PLL can be driven by HSI/2, HSE, or HSE/2
An 6 or 12 MHz TCXO would also work.
