64Kbit parallel SRAM, 25 ns access, 5V supply
The 7164S25YG is a 64Kbit asynchronous SRAM organized as 8K x 8 bits, with a 25 ns access time and a parallel memory interface. It operates from a single 4.5V to 5.5V supply, making it a 5V nominal part — not a 3.3V or lower-voltage core. The 25 ns access time sets the bus timing margin when interfacing with 8-bit microcontrollers, legacy DSPs, or CPLD-based memory controllers; at 40 MHz bus clock the cycle time is 25 ns, so this part runs at the edge of the timing budget with zero wait states. Packaged in a 28-SOJ (0.300-inch body width, 7.62 mm) surface-mount package — the same footprint as standard SOJ-28. The bulk packaging means the units ship in tubes or trays, not tape-and-reel; the unit price may differ from reel-quantity pricing on the same die.
Temperature grade and supply rails
Rated for 0°C to 70°C ambient (commercial temperature grade). This part is not specified for industrial (-40°C to 85°C) or automotive environments — if the BOM sees a -20°C cold start or a 105°C engine bay, this grade does not cover it. The 4.5V to 5.5V supply range includes the nominal 5V rail with ±10% tolerance; a 3.3V-only system needs a level translator or a different SRAM.