Renesas 71V3556S100PFG

Overview

71V3556S100PFG 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-throughput memory interfacing in network packet buffers and telecom line cards.

For engineers reviewing the 71V3556S100PFG datasheet, 71V3556S100PFG pinout, 71V3556S100PFG application, or 71V3556S100PFG equivalent, key selection criteria include ZBT™ burst timing compliance, 3.3V I/O tolerance, industrial temperature support (–40°C to +85°C), and compatibility with pipelined address/control register interfaces in high-speed switch fabric designs.

Technical Context

The 71V3556S100PFG implements a fully synchronous, positive-edge-triggered architecture with registered address, data, and control inputs. Its internal burst counter supports 4-word linear or interleaved sequences controlled by the LBO pin, and its ZBT™ feature eliminates dead cycles between read/write transitions via deterministic two-cycle latency.

It features three chip enables (CE1, CE2 active-low; CE2 active-high) for depth expansion, individual byte write enables (BW1–BW4), and an asynchronous OE pin that can be tied low. The device includes optional IEEE 1149.1 JTAG boundary scan (SA variant only) and a synchronous ZZ sleep mode for power reduction while retaining data.

Key Specifications

Pinout & Package

Packaged in a JEDEC-standard 100-pin plastic thin quad flatpack (TQFP), 14 mm × 20 mm body, 0.5 mm pitch, lead-free and RoHS-compliant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1356BV18 and AS7C33128P, the 71V3556S100PFG uniquely delivers 36-bit ZBT™ operation with deterministic 3.5 ns access and integrated burst sequencing-making it irreplaceable in high-throughput, low-jitter packet buffering where bus efficiency and timing predictability are critical.

Availability

71V3556S100PFG is available at Aetrix Electronics and suitable for telecom infrastructure, network switch design, and industrial protocol gateway development requiring stable component supply, long-term lifecycle assurance, and industrial-temperature performance.

Supply support for 71V3556S100PFG 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 markets.

The 71V3556S100PFG belongs to IDT's ZBT™ SRAM product line, engineered specifically for zero-latency bus turnaround in high-speed packet processing, switch fabric, and telecom line card applications demanding deterministic timing and burst efficiency.

FAQ

What is the memory organization and total capacity of the 71V3556S100PFG?

The 71V3556S100PFG is organized as 128K × 36 bits, delivering a total capacity of 4,718,592 bits (4.5 Mbit). This configuration supports 36-bit parallel data paths commonly used in network packet buffers and switch fabric interfaces, and is distinct from the 256K × 18-bit variant (71V3558S) in the same family.

Does the 71V3556S100PFG support burst mode, and how is burst order selected?

Yes, the 71V3556S100PFG supports 4-word burst mode via an on-chip counter. Burst order-linear or interleaved-is selected by the static LBO (Linear/Interleaved Burst Order) pin: LBO = low selects linear sequence; LBO = high selects interleaved. The burst advances on each rising CLK edge when ADV/LD is high.

What is the function of the three chip enable pins (CE1, CE2, CE2) on the 71V3556S100PFG?

The 71V3556S100PFG uses CE1 and CE2 as active-low enables and CE2 as an active-high enable. All three must be asserted (CE1 = L, CE2 = L, CE2 = H) to select the device. This triple-enable scheme allows flexible depth expansion and hierarchical chip selection in multi-SRAM systems without additional decode logic.

How does the ZBTTM feature eliminate dead cycles in the 71V3556S100PFG?

The ZBTTM (Zero Bus Turnaround) feature in the 71V3556S100PFG removes idle cycles between consecutive read and write operations by ensuring deterministic two-cycle latency and overlapping bus control. Unlike conventional SRAMs, it permits immediate read-after-write or write-after-read transitions without bus contention or turnaround delays.

Is the 71V3556S100PFG available in industrial temperature grade, and what is the range?

Yes, the 71V3556S100PFG is qualified for industrial temperature operation from –40°C to +85°C. This rating is explicitly confirmed in the Absolute Maximum Ratings and Recommended Operating Conditions tables, making it suitable for deployment in telecom line cards, base station equipment, and factory automation systems exposed to wide ambient variations.