The STM32F423xH from STMicroelectronics is a Space Qualified Microcontroller with Clock Rate 32 kHz to 26 MHz, Operating Frequency 100 MHz, Internal RAM Memory SRAM : 320 kB, Flash Memory 1536 kB, Supply Voltage 1.7 to 3.6 V. Tags: Surface Mount. More details for STM32F423xH can be seen below.