BUY M5M44256BJ-8 https://www.utsource.net/itm/p/4843468.html
Fast Page DRAM, 256KX4, 80ns, CMOS, PDSO20, 0.300 INCH, PLASTIC, SOJ-26/20
Description: 256K x 8 bit High Speed CMOS Static RAM Features: Fast access time: 70ns Low power dissipation: Active 1.5mA (max) Standby 10μA (max) Single 5V ± 10% power supply TTL compatible inputs and outputs Data retention voltage: 2.0V (min) Data retention current: 1μA (max) CMOS technology Package: SOJ-20 Application: Automotive Industrial Telecommunications Computer Consumer electronics (For reference only)