The STM32F042Fx from STMicroelectronics is a Space Qualified Microcontroller with Clock Rate 32 kHz to 48 MHz, Operating Frequency 48 MHz, Internal RAM Memory SRAM : 6 kB, Flash Memory 16 to 32 kB, Supply Voltage 2 to 3.6 V. Tags: Surface Mount. More details for STM32F042Fx can be seen below.