Static random access memory, SRAM memory, Types of Non Volatile SRAMs, nv ram

 MX29F Series 4-Mbit (512 K x 8) 70 ns 5 V Surface Mount Flash Memory - PLCC-32

https://www.futureelectronics.com/p/semiconductors--memory--flash--norflash--nor/mx29f040cqi-70gtr-macronix-4058675