LM358N by Texas Instruments is an operational amplifier with 2 functions, offering a max input offset voltage of 9000 uV and a nominal common mode reject ratio of 85 dB. Widely used in commercial applications, it operates at temperatures ranging from 0 to 70 °C and has a unity gain bandwidth of 1000 kHz.
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.