NEC D2332C-271 32Kbit 4K x 8 Mask ROM DIP-24 Vintage Memory IC NOS 1 PCS

1 PCS original NEC D2332C mask-programmed read-only memory integrated circuit in a 24-pin DIP package. Device markings include NEC, D2332C, 271, and MOY199.

The D2332C is a 32Kbit ROM organized as 4096 x 8 bits, providing 4,096 bytes of nonvolatile storage. Unlike a UV EPROM, this is a factory mask-programmed ROM. Its stored data is permanently defined during semiconductor manufacturing and cannot normally be erased and reprogrammed by the user.

The 271 marking is important because D2332C devices were produced with different factory-programmed contents for different equipment. The exact stored contents of this example have not been read or identified.

LIFECYCLE: OBSOLETE. The NEC D2332C family is a discontinued legacy mask-ROM technology from the early microprocessor era and is no longer in current production.

HISTORICAL BACKGROUND:
The NEC D2332C belongs to the generation of 4K x 8 mask ROMs widely used during the late 1970s and 1980s when microprocessor-controlled electronics were rapidly expanding.

Mask ROMs differed from programmable EPROMs because their digital contents were permanently created during semiconductor fabrication. Equipment manufacturers ordered ROMs containing specific firmware, character sets, control programs, speech data, lookup tables, or other fixed information. Different versions of the same basic D2332C could therefore contain completely different data.

The D2332C is documented in vintage computer applications, including Commodore VIC-20-family character-generator ROM applications. Devices from the D2332C family were also used in dedicated electronic systems such as early computerized chess equipment and speech-related electronics.

Because the programmed data is device-specific, surviving original mask ROMs can be particularly important when repairing vintage equipment that requires the exact ROM version rather than simply another electrically similar 4K x 8 memory device.