The CYM1441 is a very high performance 2-megabit static RAM module organized as 256K words by 8 bits. The module is constructed using eight 256K x 1 static RAMs in SOJ packages mounted onto an epoxy laminate substrate with pins. Two chip selects (CSL and CSU) are used to independently enable the upper and lower 4 bits of the data word. Writing to the memory module is accomplished when the chip select (CS) and write enable (WE) inputs are both LOW. Data on the eight input pins (DI0 through DI7) is written into the memory location specified on the address pins (A0 through A17). Reading the device is accomplished by taking chip select (CS) LOW while write enable (WE) remains inactive or HIGH. Under these conditions, the contents of the memory location specified on the address pins will appear on the appropriate data output pins (DO0 through DO7). The data output pins remain in a highimpedance state unless the module is selected and write enable (WE) is HIGH.Two pins (PD0 and PD1) are used to identify module memory density in applications where alternate versions of the JEDEC-standard modules can be interchanged.