ATMEGA328P-AU by Microchip: 8-bit RISC CPU, 20 MHz clock, 23 I/O lines. Ideal for industrial applications with SPI, TWI, USART connectivity and low power mode. Features include 2048 RAM bytes, 1024 EEPROM size, and 16384 ROM words.
MMBT3906LT1G by Onsemi is a PNP BJT with VCEsat of 0.4V, hFE of 30, and fT of 250MHz. Ideal for small signal applications in electronics due to its low power dissipation, high transition frequency, and compact SOT-23 package. Suitable for use in temperature-sensitive environments with an operating range from -65°C to 150°C.