The IDT7MP4120 is a 1M x 32 Static RAM module constructed on an epoxy laminate (FR-4) substrate using 8 1M x 4 Static RAMs in plastic packages. Availability of four chip select lines (one for each group of two RAMs) provides byte access. The IDT7MP4120 is available with access time as fast as 20ns with minimal power consumption. The IDT7MP4120 is packaged in a 72-pin FR-4 ZIP (Zigzag In-line vertical Package)or a 72-pin SIMM (Single In-line Memory Module). The ZIP configuration allows 72 pins to be placed on a package 4.05" long and 0.365" wide. At only 0.60" high, this low-profile package is ideal for systems with minimum board spacing while the SIMM configuration allows use of edge mounted sockets to secure the module. All inputs and outputs of the IDT7MP4120 are TTL-compatible and operate from a single 5V supply. Full asynchronous circuitry requires no clocks or refresh for operation and provides equal access and cycle times for ease of use. Four identification pins (PD0, PD1, PD2 and PD3) are provided for applications in which different density versions of the module are used. In this way, the target system can read the respective levels of PD0, PD1, PD2 and PD3 to determine a 1M depth.