The MR27V402D is a 4Mbit electrically Programmable Read-Only Memory whose configuration can be electrically switched between 262,144 word x 16bit and 524,288 word x 8bit. The MR27V402D operates on a single +3V-3.3V power supply and is TTL compatible. Since the MR27V402D operates asynchronously , external clocks are not required , making this device easy-to-use. The MR27V402D 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 40-pin DIP, 40-pin SOP or 44-pin TSOP packages.