This part is a kind of semiconductor called 3851.

Function of this product has SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER.

Manufacturers : Renesas

Image and pinout :

Some of the text within the PDF file :

3851 Group (Built-in 24 KB or more ROM) SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER REJ03B0066-0101Z Rev.1.01 Oct 15, 2003 DESCRIPTION The 3851 group (built-in 24 KB or more ROM) is the 8-bit microcomputer based on the 740 family core technology. The 3851 group (built-in 24 KB or more ROM) is designed for the household products and office automation equipment and includes serial I/O functions, 8-bit timer, I2C-BUS interface, and A-D converter. FEATURES Basic machine-language instructions . 71 Minimum instruction execution time . 0.5 µs (at 8 MHz oscillation frequency) Memory size ROM 24K to 32K bytes RAM ... [ ... ]

3851 PDF Datasheet Download