Renesas 71V3556S100PFGI

Overview

71V3556S100PFGI from IDT (now Renesas) is a 128K × 36-bit, 4.5 Mbit, 3.3V synchronous ZBT™ SRAM with zero bus turnaround, pipelined outputs, and 4-word burst capability. It operates at 166 MHz with 3.5 ns clock-to-data access, supports individual byte write control (BW1–BW4), and features JTAG boundary scan (IEEE 1149.1). It is used in high-speed networking buffers and packet-switching ASIC/FPGA interfaces.

For engineers reviewing the 71V3556S100PFGI datasheet, 71V3556S100PFGI pinout, 71V3556S100PFGI application, or 71V3556S100PFGI equivalent, key selection criteria include ZBT™ timing compliance, TQFP-100 package compatibility, industrial temperature support (–40°C to +85°C), and synchronous burst read/write behavior with ADV/LD and LBO control.

Technical Context

The 71V3556S100PFGI implements a fully synchronous, positive-edge-triggered architecture with registered address, data, and control inputs. Its ZBT™ feature eliminates dead cycles between read and write operations by enabling immediate bus direction reversal without wait states.

It integrates an on-chip 4-word burst counter with linear/interleaved sequencing selected via LBO, pipelined input/output registers synchronized to CLK, and three chip enables (CE1, CE2, CE2) for depth expansion. Output enable (OE) remains asynchronous while all other I/Os are clocked.

Key Specifications

Pinout & Package

71V3556S100PFGI is packaged in a 100-pin thin quad flatpack (TQFP), JEDEC MO-140, 14 mm × 20 mm body, 0.5 mm pitch. Pin 1 is located at top-left corner per standard orientation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1356BV33-133AXC and AS7C33128PFSI-10BIN, the 71V3556S100PFGI delivers higher bandwidth (166 MHz vs. ≤133 MHz), deterministic ZBT™ timing for bus efficiency, and integrated JTAG for production test coverage-making it optimal for high-reliability, high-throughput embedded systems.

Availability

71V3556S100PFGI is available at Aetrix Electronics and suitable for high-speed network packet buffers, FPGA-based protocol accelerators, and telecom baseband processing requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 71V3556S100PFGI 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 timing, memory interface, and high-performance SRAM solutions for communications and computing infrastructure.

The 71V3556S100PFGI belongs to IDT's ZBT™ SRAM product line, designed specifically for zero-turnaround, burst-capable memory subsystems in ASIC/FPGA-based networking, storage, and signal processing equipment.

FAQ

What is the maximum operating frequency of the 71V3556S100PFGI?

The 71V3556S100PFGI is rated for a maximum clock frequency of 166 MHz under industrial conditions (–40°C to +85°C) with 3.3 V ±5% supply. This enables a 6 ns cycle time and guarantees 3.5 ns clock-to-data access timing, making it suitable for high-throughput packet buffering and real-time signal processing applications where deterministic latency is critical.

Does the 71V3556S100PFGI support burst read and write operations?

Yes, the 71V3556S100PFGI supports 4-word synchronous burst operations in both linear and interleaved sequences, selected via the LBO pin. Burst mode is initiated using the ADV/LD signal: LOW loads a new address, HIGH advances the internal counter. Each burst cycle delivers or accepts four consecutive words from the memory array without reissuing the address, reducing bus overhead significantly in streaming applications.

What is the function of the ZZ pin on the 71V3556S100PFGI?

The ZZ pin on the 71V3556S100PFGI is a synchronous sleep mode input. When driven HIGH, it internally gates the CLK signal and places the device in its lowest-power state while guaranteeing data retention. This feature enables dynamic power management in battery-sensitive or thermally constrained systems, with wake-up occurring on the next valid CLK edge after ZZ returns LOW.

How does the ZBT™ feature improve system performance in the 71V3556S100PFGI?

The ZBT™ (Zero Bus Turnaround) feature in the 71V3556S100PFGI eliminates idle cycles between alternating read and write operations. Unlike conventional SSRAMs requiring turnaround time to change bus direction, the 71V3556S100PFGI allows immediate back-to-back reads and writes-enabling sustained 166 MHz bus utilization and improving effective bandwidth by up to 25% in mixed-access workloads like packet forwarding engines.

Is JTAG boundary scan supported on the 71V3556S100PFGI?

Yes, the 71V3556S100PFGI includes IEEE 1149.1-compliant JTAG boundary scan functionality. Pins TMS, TDI, TCK, TDO, and optional TRST are assigned in BGA packages; in the TQFP-100 variant (71V3556S100PFGI), these pins are NC but the underlying silicon supports the feature in SA versions. The JTAG interface enables automated PCB interconnect testing and in-system diagnostics during manufacturing and field maintenance.