Renesas 71V547S80PFGI

Overview

71V547S80PFGI from IDT (now part of Renesas) is a 3.3V, 128K × 36-bit synchronous SRAM with Zero Bus Turnaround (ZBT™) architecture, flow-through outputs, and 4-word burst capability. It delivers 95 MHz operation (8 ns clock-to-data access), supports linear/interleaved burst ordering via LBO pin, and enables seamless read/write transitions without dead cycles - ideal for high-bandwidth packet buffering in network switches and telecom line cards.

For engineers reviewing the 71V547S80PFGI datasheet, 71V547S80PFGI pinout, 71V547S80PFGI application, or 71V547S80PFGI equivalent, key selection criteria include ZBT timing compliance, 100-pin TQFP package compatibility, 3.3V ±5% supply tolerance, industrial temperature support (–40°C to +85°C), and byte-write granularity across four 9-bit I/O groups.

Technical Context

The 71V547S80PFGI implements a synchronous, clock-driven interface where address/control registration occurs on the rising CLK edge under valid CE and CEN conditions. Its ZBT™ operation eliminates bus turnaround latency by allowing immediate read-after-write or write-after-read transitions using ADV/LD to control burst counter advancement versus new address loading.

It features three chip enables (CE1, CE2 low-active; CE2 high-active) for flexible depth expansion, asynchronous OE for output tri-state control, and static LBO pin selection between linear and interleaved 4-word burst sequences - all while maintaining flow-through (unregistered) data outputs for minimal read latency.

Key Specifications

Pinout & Package

71V547S80PFGI is packaged in a JEDEC-standard 100-pin thin quad flatpack (TQFP), 14 mm × 20 mm body, 0.5 mm pitch. Pin 1 marked by dot; top-side marking includes "71V547S80PFGI" and date code.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1355BV18-167BZC and AS7C312836B-10BIN, the 71V547S80PFGI uniquely combines ZBT™ timing, 4-word burst, and industrial temperature support in a drop-in 100-pin TQFP footprint - making it irreplaceable for legacy telecom and networking hardware requiring zero-turnaround latency without architectural redesign.

Availability

71V547S80PFGI is available at Aetrix Electronics and suitable for network packet buffering, telecom line card memory, industrial PLC data logging, and avionics data acquisition requiring stable component supply across extended product lifecycles.

Supply support for 71V547S80PFGI 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, RF, and high-performance interconnect solutions.

The 71V547S80PFGI belongs to IDT's ZBT™ SRAM family, engineered specifically for high-speed communications infrastructure where deterministic latency, burst efficiency, and bus turnaround elimination are mandatory for wire-speed packet processing.

FAQ

What is the maximum operating frequency of the 71V547S80PFGI?

The 71V547S80PFGI is rated for 95 MHz operation, corresponding to a minimum clock cycle time (tCYC) of 10.5 ns. This specification is guaranteed across the full industrial temperature range (–40°C to +85°C) and 3.3V ±5% supply voltage. The 'S80' suffix denotes the 8 ns clock-to-data access timing bin, confirming its suitability for high-throughput data-path applications requiring tight timing closure.

Does the 71V547S80PFGI support true ZBT™ (Zero Bus Turnaround) operation?

Yes, the 71V547S80PFGI implements genuine ZBT™ functionality as defined by Renesas/IDT. It eliminates dead cycles between read and write operations by using the ADV/LD signal to distinguish between loading a new address (ADV/LD = LOW) and advancing the internal burst counter (ADV/LD = HIGH). This allows immediate read-after-write or write-after-read transitions without bus idle periods - a verified feature confirmed in the functional description and timing waveforms of the official datasheet.

What is the role of the LBO pin on the 71V547S80PFGI?

The LBO (Linear Burst Order) pin on the 71V547S80PFGI is a static DC input that selects the 4-word burst sequence: LOW configures linear order (A0, A1, A2, A3), while HIGH selects interleaved order (A0, A2, A1, A3). This pin directly maps to industry-standard burst protocols used by CPUs and network processors, enabling seamless integration without software remapping. Its static nature means it can be hardwired to VSS or VDD, eliminating dynamic control overhead.

How does the 71V547S80PFGI handle byte-level writes?

The 71V547S80PFGI supports individual byte writes via four active-low synchronous signals: BW1, BW2, BW3, and BW4. Each controls a 9-bit group - BW1 covers I/O[0:7] and I/OP1, BW2 covers I/O[8:15] and I/OP2, and so on. During a write cycle (R/W = LOW), only the byte groups with asserted BWx signals are updated; others retain prior data. This eliminates need for external read-modify-write logic and reduces bus traffic in partial-update scenarios.

Is the 71V547S80PFGI pin-compatible with other members of the 71V547 family?

Yes, the 71V547S80PFGI is fully pin-compatible with other speed grades in the 71V547 family (e.g., 71V547S85PFGI, 71V547S90PFGI), sharing identical 100-pin TQFP packaging, pinout, and electrical interface. Differences are limited to AC timing parameters (e.g., tCD, tCYC) and operating frequency limits - allowing direct substitution in existing designs when performance headroom or temperature margin requirements change.