Renesas 71V65903S80PFGI8

Overview

71V65903S80PFGI8 from IDT (now Renesas) is a 3.3V synchronous ZBT™ SRAM organized as 512K × 18 bits (9,437,184-bit capacity), supporting 100 MHz operation with 7.5 ns clock-to-data access, zero bus turnaround (ZBT) architecture, and flow-through outputs. It serves as high-speed buffer/cache memory in networking switches, packet processors, and FPGA-based data-path subsystems requiring burst read/write without dead cycles.

For engineers reviewing the 71V65903S80PFGI8 datasheet, 71V65903S80PFGI8 pinout, 71V65903S80PFGI8 application, or 71V65903S80PFGI8 equivalent, key selection criteria include its 100 MHz synchronous timing, 4-word interleaved/linear burst capability, individual byte write control (BW1–BW2), industrial temperature range (–40°C to +85°C), and TQFP-100 packaging with 3.3V core/I/O supplies.

Technical Context

The 71V65903S80PFGI8 implements a synchronous dual-edge-triggered interface with a dedicated burst counter controlled by ADV/LD and LBO pins, enabling deterministic 4-word burst sequences either linear or interleaved. Its flow-through output architecture eliminates output registers, reducing read latency while relying on external OE for asynchronous output control.

It features three chip enables (CE1, CE2 active-low; CE2 active-high) for depth expansion, Clock Enable (CEN) for full-cycle suspension, and ZZ sleep mode for low-power retention. All address, control, and data-in signals are registered on the rising CLK edge, with strict setup/hold timing referenced solely to that edge.

Key Specifications

Pinout & Package

71V65903S80PFGI8 is packaged in a JEDEC-standard 100-pin plastic thin quad flatpack (TQFP), 14 mm × 20 mm body, with 0.5 mm lead pitch. Pin functions are fully defined per the 512K × 18 configuration - note that A18 is used (vs. A17 in 256K × 36 variant), and BW3/BW4 are NC.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous SRAM applications.

Compared with CY7C1371DV33-100AXC and AS7C35128PFS-10BIN, the 71V65903S80PFGI8 uniquely delivers zero-turnaround burst transfers with minimal control logic - critical for deterministic latency in packet buffering and real-time control where back-to-back accesses dominate.

Availability

71V65903S80PFGI8 is available at Aetrix Electronics and suitable for network packet buffering, FPGA co-processor caching, telecom baseband processing, and industrial motion controller buffer applications requiring stable component supply across long production lifecycles.

Supply support for 71V65903S80PFGI8 includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

IDT (Integrated Device Technology), now part of Renesas Electronics, is a fabless semiconductor company specializing in high-performance timing, memory, and interface solutions for communications and computing infrastructure.

The 71V65903S80PFGI8 belongs to IDT's ZBT™ SRAM product line, designed specifically for high-speed data-path applications demanding deterministic burst access, zero bus turnaround, and industrial-grade reliability in telecom and networking equipment.

FAQ

What is the memory organization of the 71V65903S80PFGI8?

The 71V65903S80PFGI8 is organized as 512K × 18 bits (9,437,184 total bits), meaning it has 524,288 addressable words, each 18 bits wide. This configuration uses address lines A0–A18 and supports only the x18 data bus mode - distinct from the 256K × 36 variant (71V65703) which shares the same pinout but different internal mapping. The 71V65903S80PFGI8 does not support x36 operation.

Does the 71V65903S80PFGI8 support burst read and write operations?

Yes, the 71V65903S80PFGI8 supports 4-word synchronous burst operations for both reads and writes. Burst mode is initiated by sampling ADV/LD = HIGH after an initial load cycle (ADV/LD = LOW). The sequence order - linear or interleaved - is selected by the static LBO pin. Burst transfers occur automatically without additional address inputs, reducing bus overhead and improving effective bandwidth in streaming applications.

What is the function of the ZZ pin on the 71V65903S80PFGI8?

The ZZ pin on the 71V65903S80PFGI8 is an asynchronous active-high sleep mode input. When asserted, it gates the internal clock and places the device in low-power retention mode while maintaining data integrity. VDD must remain applied; current draw drops significantly, and all outputs go high-impedance. ZZ is internally pulled to VSS if left unconnected, so external pull-down is not required unless active control is needed.

How many byte write enable signals are functional in the 71V65903S80PFGI8?

In the 71V65903S80PFGI8 (512K × 18 configuration), only BW1 and BW2 are functional - controlling 9-bit bytes I/O[0:8]/I/OP1 and I/O[9:17]/I/OP2 respectively. BW3 and BW4 are No Connect (NC) per the 512K × 18 pinout diagrams and truth tables. This differs from the 256K × 36 variant (71V65703), where all four BWx signals are active for 36-bit writes.

Is the 71V65903S80PFGI8 pin-compatible with other members of the 71V65703/65903 family?

Yes, the 71V65903S80PFGI8 is pin-compatible with the 71V65703 in the same 100-pin TQFP package - sharing identical pin assignments for power, clock, control, and I/O. However, internal functionality differs: the 71V65903S80PFGI8 uses A18 and disables BW3/BW4, while the 71V65703 uses A17 and enables all four BWx signals. PCB layout may be reused, but firmware and timing constraints must reflect the x18 organization.