Renesas 71V632S5PFG

Overview

71V632S5PFG from IDT is a 3.3V synchronous SRAM organized as 64K × 32 (2,097,152 bits), featuring pipelined outputs, single-cycle deselect, and burst counter logic. It supports 100 MHz operation with 5.5 ns clock access time, operates across commercial (0°C to +70°C) and industrial (–40°C to +85°C) temperature ranges, and interfaces directly with Pentium™ and PowerPC™ processors for secondary cache applications.

For engineers reviewing the 71V632S5PFG datasheet, 71V632S5PFG pinout, 71V632S5PFG application, or 71V632S5PFG equivalent, key selection criteria include its 100-pin TQFP package, 3.3V-only supply, pipelined burst read timing, self-timed write control via GW/BWE/BWx, and LBO-selectable linear/interleaved burst mode - all critical for high-speed cache subsystem design.

Technical Context

The 71V632S5PFG implements a synchronous, pipelined architecture with internal address register, burst counter, and output register stages. Its clock-driven interface synchronizes address, control, and data transfers on rising CLK edges, enabling deterministic timing for processor coherency.

Burst operation is initiated by ADSP/ADSC and controlled by ADV and LBO inputs; the internal binary counter generates sequential addresses for four-word bursts. Write cycles are self-timed using global write (GW) or byte-write enable (BWE) with independent BW1–BW4 controls, supporting partial writes without external timing management.

Key Specifications

Pinout & Package

Packaged in a JEDEC-standard 100-pin thin quad flatpack (TQFP), 14 mm × 20 mm body size, with 0.5 mm lead pitch. Pin 1 marked by dot; pins 14 and 64 are NC/VDD configurable per application requirements.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1370D-133AXC and AS7C3256A-15JCN, the 71V632S5PFG uniquely balances 100 MHz burst performance, pipelined latency, 3.3V simplicity, and TQFP compatibility - making it optimal for retrofitting Pentium/PowerPC-era designs without architectural overhaul.

Availability

71V632S5PFG is available at Aetrix Electronics and suitable for desktop CPU cache modules, industrial PLC data buffers, and legacy embedded controller upgrades requiring stable component supply and long-term lifecycle support.

Supply support for 71V632S5PFG 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) was a fabless semiconductor company specializing in timing, memory, and interface ICs before its acquisition by Renesas in 2019. Known for high-performance SRAMs and clock solutions serving computing and communications markets.

The 71V632S5PFG belongs to IDT's 71V family of pipelined synchronous SRAMs, designed specifically to meet the burst-access and low-latency requirements of Pentium and PowerPC secondary cache subsystems in late-1990s/early-2000s computing platforms.

FAQ

Is the 71V632S5PFG still in production or considered obsolete?

The 71V632S5PFG is marked OBSOLETE and NOT RECOMMENDED FOR NEW DESIGNS per IDT documentation. However, Aetrix Electronics maintains verified legacy inventory with full traceability and offers extended supply support for ongoing production and repair programs requiring this specific speed grade and package configuration.

What is the functional difference between ADSP and ADSC on the 71V632S5PFG?

On the 71V632S5PFG, ADSP (Address Strobe Pulse) and ADSC (Address Strobe Complement) are functionally interchangeable for read operations - both trigger address latching and burst initiation on their falling edge. For write cycles, ADSP initiates burst writes while ADSC supports non-burst writes, per the synchronous truth table.

Does the 71V632S5PFG support true 100 MHz operation across the full industrial temperature range?

Yes - the 71V632S5PFG-100 speed grade (denoted by 'S5' in 71V632S5PFG) guarantees 5.5 ns clock access time at 100 MHz over –40°C to +85°C. This is validated in AC Electrical Characteristics tables and confirmed by tCD = 4.5 ns (SA4 speed grade) under industrial conditions.

Can the 71V632S5PFG operate with only VDD powered, or are VDDQ and VSSQ required?

VDDQ and VSSQ must be independently connected - they supply the I/O buffer domain and are not internally tied to VDD/VSS. Omitting VDDQ/VSSQ will result in undefined I/O behavior and potential bus contention. The datasheet specifies separate 3.3V ±5% supplies for VDD (core) and VDDQ (I/O), each with dedicated decoupling.

How does the LBO pin affect burst address sequencing in the 71V632S5PFG?

The LBO pin selects burst order: when tied to VSS, the 71V632S5PFG uses linear burst (00→01→10→11); when tied to VDD, it uses interleaved burst (00→10→01→11). This matches Pentium (interleaved) and PowerPC (linear) cache line fill conventions - no external logic is needed to adapt to either architecture.