The PIC16F84AT-20I/SO from MICROCHIP TECH. is PIC 16F family 18-Pin SOIC enhanced FLASH/EEPROM 8-Bit microcontroller. The PIC16F84AT-20I/SO microcontroller has 1.75KB (1K x 14) FLASH program memory, 64 x 8 EEPROM data memory, 68 x 8 RAM size and 13 I/O general-purpose I/O pins. This microcontroller operates at a maximum frequency of 20MHz with operating voltage of 4 to 5.5V. Operating temperature range is from -40°C to 85°C.