32-bit ARM Cortex-M3 MCU, 256KB Flash, 32MHz, 37 I/O, 48-pin QFN
32-bit ARM Cortex-M3 MCU, 256KB Flash, 32MHz, USB, UFQFPN
32-bit Cortex-M3 MCU, 256KB Flash, 32MHz, USB, 48-Pin PQFP
