MMSZ5245BT1G by Onsemi is a Zener diode with 15V nominal reference voltage, 8.5mA test current, and 16 ohm dynamic impedance. It is used in applications requiring precise voltage regulation in a compact SMD package for temperatures ranging from -55 to 150°C.
STM32F401CDY6TR by STMicroelectronics is a 32-bit microcontroller with 393216 ROM words, 50 MHz clock frequency, and 36 I/O lines. It is used in applications requiring high-speed processing, such as industrial automation and consumer electronics.