Renesas 71V2556S133PFGI

Overview

71V2556S133PFGI from IDT (now Renesas) is a 3.3V synchronous ZBT™ SRAM with 128K × 36-bit organization (4.5 Mbit), 133 MHz operation (7.5 ns clock-to-data access), pipelined outputs, and zero-bus-turnaround architecture for high-throughput memory subsystems in network packet buffers and telecom line cards.

For engineers reviewing the 71V2556S133PFGI datasheet, 71V2556S133PFGI pinout, 71V2556S133PFGI application, or 71V2556S133PFGI equivalent, key selection criteria include burst mode support (linear/interleaved), individual byte write control (BW1–BW4), 2.5V I/O voltage compatibility, industrial temperature range (–40°C to +85°C), and JEDEC-standard 100-pin TQFP packaging.

Technical Context

The 71V2556S133PFGI implements a fully synchronous, clock-edge-triggered interface with address, data, and control registers aligned to the rising edge of CLK. Its internal burst counter enables 4-word bursts per address load, selected via LBO pin for linear or interleaved sequences.

ZBT™ operation eliminates dead cycles between read/write transitions by overlapping bus turnaround with valid data transfer; OE is internally synchronized, removing external timing constraints on output enable. CEN provides clock gating for power management without register state loss.

Key Specifications

Pinout & Package

71V2556S133PFGI is packaged in a 100-pin TQFP (PKG100) with 0.5 mm pitch, compliant with JEDEC MO-147. Pin 64 supports ZZ (sleep mode) on latest die revision; pins 14, 16, and 66 require ≥VIH but not direct VDD connection.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1356BV133BZC and AS7C3256B-133JCIN, the 71V2556S133PFGI uniquely combines 2.5V I/O isolation, ZZ sleep mode, and selectable burst order - critical for power-constrained, mixed-voltage telecom designs requiring testability and thermal robustness.

Availability

71V2556S133PFGI is available at Aetrix Electronics and suitable for network packet buffering, telecom line card memory, base station baseband processing, and industrial PLC data logging requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 71V2556S133PFGI 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, specializes in high-performance timing, memory, and interface solutions for communications and computing infrastructure.

The 71V2556S133PFGI belongs to IDT's ZBT™ SRAM product line, engineered specifically for zero-latency, high-bandwidth memory subsystems in networking ASICs, telecom line cards, and real-time signal processing platforms.

FAQ

What is the maximum operating frequency of the 71V2556S133PFGI?

The 71V2556S133PFGI is rated for 133 MHz operation, delivering a guaranteed 7.5 ns clock-to-data access time under industrial temperature and voltage conditions. This frequency supports sustained high-throughput data buffering in telecom and networking equipment where deterministic latency is critical. The 71V2556S133PFGI achieves this using fully pipelined synchronous architecture with edge-triggered registers.

Does the 71V2556S133PFGI support burst mode, and how is it configured?

Yes, the 71V2556S133PFGI supports 4-word burst mode with selectable linear or interleaved sequencing. Configuration is controlled by the LBO (Linear/Interleaved Burst Order) pin: LBO = VSS selects linear order (A0, A1, A2, A3), while LBO = VDD selects interleaved (A0, A2, A1, A3). The ADV/LD pin loads the initial address or advances the internal burst counter. This capability is integral to the 71V2556S133PFGI's role in cache-coherent and packet-processing systems.

What is the purpose of the ZZ (sleep) mode in the 71V2556S133PFGI?

The ZZ (sleep) mode in the 71V2556S133PFGI reduces standby current to less than 5 µA by placing the device in a low-power state while retaining memory contents. Pin 64 serves as the ZZ input on the latest die revision and must be driven high to enter sleep mode. This feature is essential for energy-sensitive applications like remote base stations and battery-backed industrial controllers where the 71V2556S133PFGI operates intermittently.

How does the 71V2556S133PFGI handle byte-level write operations?

The 71V2556S133PFGI provides four dedicated byte write enable inputs - BW1 through BW4 - each controlling an 8-bit segment of the 32-bit data bus (I/O[0:7], [8:15], [16:23], [24:31]). When asserted low, the corresponding byte is written; others remain unchanged. This eliminates the need for external read-modify-write circuitry and is a core feature of the 71V2556S133PFGI's design for efficient partial-word updates in protocol stacks and control registers.

Is the 71V2556S133PFGI compatible with JTAG boundary scan testing?

The 71V2556S133PFGI includes optional IEEE 1149.1 JTAG boundary scan support, implemented via dedicated pins (TMS, TDI, TCK, TDO, TRST) that are NC on the "S" version but functional on the "SA" variant. For the 71V2556S133PFGI specifically, JTAG is not enabled - those pins are no-connect. This distinguishes it from the SA variant and confirms the 71V2556S133PFGI's focus on cost-optimized, non-test-intensive applications.