The MR27V401D is a 4Mbit electrically Programmable Read-Only Memory organized as 524,288 word x 8bit. The MR27V401D operates on a single +3V-3.3V power supply and is TTL compatible. Since the MR27V401D operates asynchronously , external clocks are not required , making this device easy-to-use. The MR27V401D is suitable as large-capacity fixed memory for microcomputers and data terminals. It is manufactured using a CMOS double silicon gate technology and is offered in 32-pin DIP, 32-pin SOP or 32-pin TSOP packages.