Renesas 71V3556S100PFG8

Overview

71V3556S100PFG8 from IDT (now Renesas) is a 3.3V synchronous ZBT™ SRAM with 128K × 36-bit organization (4.5 Mbit), 166 MHz operation, 3.5 ns clock-to-data access, zero bus turnaround architecture, and pipelined outputs in a 100-pin TQFP package. It enables high-bandwidth memory interfacing in network packet buffers and cache subsystems.

For engineers reviewing the 71V3556S100PFG8 datasheet, 71V3556S100PFG8 pinout, 71V3556S100PFG8 application, or 71V3556S100PFG8 equivalent, key selection criteria include ZBT™ burst timing, 4-word interleaved/linear burst capability, individual byte write control (BW1–BW4), JTAG support (optional), and industrial temperature range compatibility.

Technical Context

The 71V3556S100PFG8 implements a fully synchronous, positive-edge-triggered architecture with address/control/data registers clocked on CLK rising edge. Its ZBT™ feature eliminates dead cycles between read/write transitions via internal burst counter and ADV/LD-controlled address loading or incrementing.

It supports dual-bus-turnaround modes: linear or interleaved burst sequences selected by LBO pin, and features three chip enables (CE1, CE2, CE2) for depth expansion, plus asynchronous OE for output tri-state control independent of clock timing.

Key Specifications

Pinout & Package

71V3556S100PFG8 is packaged in a JEDEC-standard 100-pin plastic thin quad flatpack (TQFP), 14 mm × 20 mm body size, with 0.5 mm pitch leads.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 71V3556S100PFG8, the SA variant adds JTAG for testability without performance trade-offs, while AS7C3256B-15JIN offers lower cost and power at the expense of ZBT™ efficiency and burst capability-making it viable only in non-critical throughput applications.

Availability

71V3556S100PFG8 is available at Aetrix Electronics and suitable for network packet buffers, telecom line card memory, and industrial real-time controller buffers requiring stable component supply and long-term industrial temperature support.

Supply support for 71V3556S100PFG8 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 semiconductor company specializing in high-performance timing, memory, and interface solutions for communications and computing infrastructure.

The 71V3556S100PFG8 belongs to IDT's ZBT™ SRAM product line, designed specifically for high-throughput, low-latency memory interfacing in networking ASICs, packet switches, and real-time embedded systems demanding deterministic timing.

FAQ

What is the memory organization and total capacity of the 71V3556S100PFG8?

The 71V3556S100PFG8 is organized as 128K × 36 bits, delivering a total capacity of 4,718,592 bits (4.5 Mbit). This configuration supports 36-bit wide data paths common in high-speed packet processing and cache subsystems, eliminating the need for external width expansion in many applications.

Does the 71V3556S100PFG8 support burst read and write operations?

Yes, the 71V3556S100PFG8 supports 4-word burst operations in both linear and interleaved sequences, controlled by the LBO pin. Burst mode reduces address bus activity and improves effective bandwidth-critical for applications like network packet buffering where sequential data access dominates.

What is the function of the ADV/LD pin on the 71V3556S100PFG8?

The ADV/LD pin on the 71V3556S100PFG8 controls the internal burst counter: when sampled LOW at the rising CLK edge, it loads a new external address; when HIGH, it advances the counter to the next burst address. This dual-mode operation enables flexible burst initiation and chaining without external address generation logic.

Is JTAG boundary scan supported on the 71V3556S100PFG8?

No, the 71V3556S100PFG8 does not include JTAG boundary scan. That feature is available only on the "SA" variant (e.g., 71V3556SA100PFG8). The "S" suffix indicates the standard version without IEEE 1149.1 test circuitry, though pin-compatible with SA in TQFP packaging.

What is the role of the ZZ (Sleep Mode) pin on the 71V3556S100PFG8?

The ZZ pin on the 71V3556S100PFG8 is an active-high synchronous input that gates the internal clock and places the device into low-power sleep mode while guaranteeing data retention. When asserted, it reduces dynamic power consumption significantly-ideal for power-aware telecom and industrial applications with intermittent memory access patterns.