The CYM1836 is a high-performance 4-megabit static RAM module organized as 128K words by 32 bits. This module is constructed from four 128K x 8 SRAMs in SOJ packages mounted on an epoxy laminate board with pins. Four chip selects (CS₁, CS₂, CS₃, CS₄) are used to independently enable the four bytes. Reading or writing can be executed on individual bytes or any combination of multiple bytes through proper use of selects.

Writing to each byte is accomplished when the appropriate Chip Select (CS) and Write Enable (WE) inputs are both LOW. Data on the input/output pins (I/O) is written into the memory location specified on the address pins (A₀ through A₁₆).

Reading the device is accomplished by taking the Chip Select (CS) LOW while Write Enable (WE) remains HIGH. Under these conditions, the contents of the memory location specified on the address pins will appear on the data input/output pins (I/O).

The data input/output pins stay at the high-impedance state when write enable is LOW or the appropriate chip selects are 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.