71V2556S166PFG

Overview

The 71V2556S166PFG is a 3.3V CMOS synchronous pipelined SRAM organized as 128K x 36, featuring Zero Bus Turnaround (ZBT) technology to eliminate dead bus cycles during read/write transitions. It operates with a 2.5V I/O supply and supports clock frequencies up to 166 MHz. The device includes data I/O, address, and control signal registers, providing four cycles of data for a single address. It is available in a 100-pin TQFP package and offers an optional boundary scan JTAG interface compliant with IEEE 1149.1.

Feature Summary

• Zero Bus Turnaround architecture eliminates dead bus cycles between read and write operations
• Synchronous pipelined design provides four cycles of data for a single address
• Optional boundary scan JTAG interface for testing compliance

Applications

• High-performance processor secondary cache systems
• Network infrastructure equipment requiring low-latency memory
• Industrial automation controllers needing fast data buffering

Procurement Notes

Verify component status as the 71V2556 series has been discontinued by Renesas Electronics Corporation. Confirm availability through authorized distributors or surplus channels. Check for moisture sensitivity level (MSL 3) handling requirements during storage and assembly. Ensure compatibility with existing PCB footprints for the 100-pin TQFP package before procurement.

Selection Notes

Select this component for applications requiring high-speed synchronous memory with minimal turnaround latency. The ZBT feature is critical for systems where bus efficiency impacts overall throughput. Verify voltage levels match the system's 3.3V core and 2.5V I/O requirements. Consider the pipelined output structure for timing optimization in high-frequency designs.

Part Context

The 71V2556S166PFG belongs to the Renesas 71V2556 family of ZBT synchronous SRAMs. This family is designed to replace traditional asynchronous SRAMs in high-speed digital systems. The specific suffix indicates the speed grade (166 MHz) and package type (TQFP). It is part of Renesas' broader portfolio of memory solutions for embedded processing.

Replacement Considerations

Public confirmed substitute part numbers include 71V2556S150PFGI and 71V2556S133PFGI from Renesas. These variants offer similar ZBT functionality but with different maximum clock frequencies. Verify pinout and electrical specifications against the original design requirements when substituting.