Features: ARM 32-bit Cortex-M3 CPU core, maximum frequency 72 MHz, performance of 1.25 DMIPS/MHz (Dhrystone 2.1) at 0-wait-state memory access, supports single-cycle multiplication and hardware division. 64 or 128 Kbytes of flash and 20 Kbytes of SRAM. Clock, reset and power management: 2.0 to 3.6 V application power and I/O, POR, PDR and programmable voltage detector (PVD), 4 to 16 MHz crystal oscillator, internal 8 MHz factory-calibrated RC, internal 40 kHz RC, PLL for CPU clock, calibrated 32 kHz oscillator for RTC. Low power: sleep, stop and standby modes, VBAT powers RTC and backup registers. 2 x 12-bit, 1 µs A/D converters (up to 16 channels), conversion range: 0 to 3.6 V, dual sampling and hold capability, temperature sensor. 7-channel DMA controller, supported peripherals: timers, ADC, SPI, I²C and USART