Renesas 71V65703S85BQ

Overview

71V65703S85BQ from IDT (now Renesas) is a 3.3V synchronous ZBT™ SRAM organized as 256K × 36 (9.44 Mbit), supporting 100 MHz operation with 7.5 ns clock-to-data access, zero bus turnaround between read/write cycles, and flow-through outputs. It serves as high-speed buffer memory in network packet processors, telecom line cards, and FPGA-based data-path acceleration where burst throughput and deterministic latency are critical.

For engineers reviewing the 71V65703S85BQ datasheet, 71V65703S85BQ pinout, 71V65703S85BQ application, or 71V65703S85BQ equivalent, key selection criteria include ZBT™ burst capability (linear/interleaved), individual byte write control (BW1–BW4), asynchronous OE/ZZ for output disable and sleep mode, and JEDEC-standard 165-ball fine-pitch BGA (BQ) packaging compatible with industrial temperature range (–40°C to +85°C).

Technical Context

The 71V65703S85BQ implements a synchronous dual-edge-triggered architecture with registered address/control inputs and flow-through (unregistered) data outputs. Its on-chip burst counter advances on ADV/LD = HIGH, enabling four-word bursts per address load - selectable via LBO pin for linear or interleaved sequences.

It features three chip enables (CE1, CE2 active-low; CE2 active-high) for depth expansion, internal synchronization of OE to eliminate external timing control, and a dedicated ZZ input that gates CLK internally to reduce power while guaranteeing data retention in sleep mode.

Key Specifications

Pinout & Package

71V65703S85BQ is packaged in a 165-ball fine-pitch ball grid array (BQ165), compliant with JEDEC MO-245, measuring 12 mm × 12 mm with 0.8 mm ball pitch. The package supports industrial temperature operation and includes dedicated VDD, VDDQ, and VSS balls distributed for low-impedance power delivery and signal integrity.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1373KV18 and AS7C3256A, the 71V65703S85BQ delivers optimal balance of wide 36-bit bus, ZBT™ zero-turnaround efficiency, and industrial-temperature BGA packaging - making it uniquely suited for high-throughput, low-latency buffering in telecom and networking infrastructure.

Availability

71V65703S85BQ is available at Aetrix Electronics and suitable for network packet buffering, FPGA co-processor caching, telecom line card FIFOs, DSP algorithm acceleration, and industrial control data logging requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 71V65703S85BQ 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 high-performance timing, memory, and interface solutions for communications, computing, and industrial markets.

The 71V65703S85BQ belongs to IDT's ZBT™ synchronous SRAM product line, engineered specifically for applications demanding deterministic latency, burst efficiency, and seamless integration with high-speed processors and FPGAs in infrastructure equipment.

FAQ

What is the memory organization and total capacity of the 71V65703S85BQ?

The 71V65703S85BQ is organized as 256K × 36, delivering 9,437,184 bits (9.44 Mbit) of synchronous SRAM. This configuration provides a 36-bit data bus width optimized for systems requiring wide-word data transfers, such as network processors and DSP co-processors. It shares pin compatibility with the 512K × 18 variant (71V65903), allowing layout reuse across density options.

Does the 71V65703S85BQ support burst read and write operations, and how is burst order controlled?

Yes, the 71V65703S85BQ supports 4-word burst operations for both reads and writes. Burst order is selected via the LBO (Linear/Interleaved Burst Order) pin: LBO = LOW enables linear addressing (A0, A1, A2, A3), while LBO = HIGH selects interleaved order (A0, A2, A1, A3). The burst counter advances on ADV/LD = HIGH, and the R/W signal determines burst direction at initiation.

How does the ZBTTM (Zero Bus Turnaround) feature function in the 71V65703S85BQ?

ZBTTM eliminates idle cycles when switching between read and write operations. In the 71V65703S85BQ, a write cycle can be immediately followed by a read cycle (or vice versa) without inserting wait states - the bus transitions seamlessly because address/control setup and data transfer are fully pipelined. This is achieved through internal register staging and flow-through outputs, boosting effective bandwidth in ping-pong buffer architectures.

What are the power supply requirements and sleep capabilities of the 71V65703S85BQ?

The 71V65703S85BQ requires two 3.3 V supplies: VDD (core, ±5%) and VDDQ (I/O, ±5%). It features an asynchronous ZZ (sleep) input: asserting ZZ = HIGH gates the internal clock and reduces active power significantly while guaranteeing data retention across the full industrial temperature range (–40°C to +85°C). No external sequencing is required between VDD and VDDQ.

Can the 71V65703S85BQ perform partial-word writes, and how is this implemented?

Yes, the 71V65703S85BQ supports individual byte writes using four dedicated active-low signals: BW1, BW2, BW3, and BW4. Each controls a 9-bit segment of the 36-bit bus (I/O[0:7]+I/OP1 through I/O[24:31]+I/OP4). When a BWx signal is LOW during a write cycle, its corresponding byte is updated; all HIGH disables writes to that byte. This enables efficient protocol header modification without full-word read-modify-write sequences.