74LS00

The 7400 series of chips perform transistor-transistor logic. From Wikipedia, the 74LS series is "Low-power Schottky. Implemented using the same technology as 74S but with reduced power consumption and switching speed, due to larger resistors. Typical 10 ns gate delay, remarkable (for the time) 2 mW dissipation, 4.75–5.25 V." In layman's terms, on SNES PCBs, these chips link together ROM and RAM chips. The 74LS00 chips can be found on PCBs that utilize two Mask ROM chips.

GD74LS00

Chip type: 74LS00

Part #: GD74LS00

Manufacturer: GS Battery

Date format: YYWW

Variables: Date code

MB74LS00

Chip type: 74LS00

Part #: MB74LS00

Manufacturer: Fujitsu

Date format: YYWW xxx

Variables: Date code