INMOS G171S-35C RAM (Random Access Memory)

Specifications

​Manufacturer: INMOS (acquired by SGS-Thomson Microelectronics, which later became STMicroelectronics).

​Part Number: G171S-35C.

​Function: It's a color palette chip that contains a RAM (Random Access Memory) look-up table and three digital-to-analog converters (DACs), one for each of the primary colors (Red, Green, and Blue). It was designed to provide a wide range of colors (up to 256 simultaneously) on a video display.

​Technology: CMOS (Complementary Metal-Oxide-Semiconductor).

​Package: 28-pin ceramic DIP (Dual In-line Package). The gold-colored top of the chip is the die itself, which is exposed in this particular type of hermetic ceramic package. The A after the INMOS logo likely refers to the revision. The 8742 is the date code, meaning it was manufactured in the 42nd week of 1987.