Renesas 71V67703S85BQ

Overview

71V67703S85BQ from IDT (now Renesas) is a 256K × 36-bit, 3.3V synchronous SRAM with flow-through outputs, 8.5ns access time at 87MHz clock frequency, single-cycle deselect, and burst-mode operation enabled by ADV/LBO control logic. It serves as high-bandwidth data buffer in network packet processors and telecom line cards requiring deterministic latency and burst-aligned memory access.

For engineers reviewing the 71V67703S85BQ datasheet, 71V67703S85BQ pinout, 71V67703S85BQ application, or 71V67703S85BQ equivalent, key selection criteria include its 100-pin TQFP package, 3.3V core/I/O supply compatibility, linear/interleaved burst ordering via LBO, self-timed write with byte-level granularity (BW1–BW4), and industrial-grade temperature support up to +85°C.

Technical Context

The 71V67703S85BQ implements a synchronous, clock-driven architecture with registered address/data inputs and flow-through (unregistered) outputs - eliminating output register delay for minimal read-to-data timing. Its internal burst counter advances on ADV=LOW transitions, generating four consecutive addresses per initial access using either linear (LBO=LOW) or interleaved (LBO=HIGH) sequences.

Write operations are controlled synchronously via GW (global), BWE (byte enable gate), and BW1–BW4 (individual 9-bit byte selects), enabling precise 8-bit or 36-bit granularity writes without bus contention. Power management includes asynchronous ZZ input for full-sleep mode (IZZ ≤ 70mA) and CMOS standby (ISB1 ≤ 70mA) when deselected.

Key Specifications

Pinout & Package

Packaged in JEDEC-standard 100-pin thin quad flatpack (TQFP), 14mm × 20mm body, lead-free and RoHS-compliant. Pinout optimized for signal integrity with distributed VDD/VSS/VDDQ and dedicated ground planes.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1373KV18 and AS7C3256B, the 71V67703S85BQ uniquely delivers 256K×36 burst capability in TQFP with configurable LBO and flow-through outputs - making it irreplaceable for latency-critical, clock-synchronized data buffering where pin compatibility and timing predictability are mandatory.

Availability

71V67703S85BQ is available at Aetrix Electronics and suitable for network packet buffering, telecom line card memory, baseband processing cache, and industrial PLC data exchange requiring stable component supply and long-term industrial-grade availability.

Supply support for 71V67703S85BQ 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

Renesas Electronics (formerly Integrated Device Technology) is a global semiconductor leader specializing in high-performance memory, analog, and embedded solutions for communications, industrial, and automotive markets.

The 71V67703S85BQ belongs to IDT's high-speed synchronous SRAM product line, designed specifically for deterministic-latency, burst-capable memory subsystems in networking infrastructure and real-time embedded systems.

FAQ

What is the maximum operating frequency of the 71V67703S85BQ?

The 71V67703S85BQ is rated for operation up to 87MHz clock frequency, corresponding to an 8.5ns access time (tCD). This specification is guaranteed over the full industrial temperature range (–40°C to +85°C) and 3.3V ±5% supply conditions. The device supports lower-speed grades (100MHz/8.0ns and 117MHz/7.5ns) in other variants, but the 'S85' suffix confirms the 87MHz/8.5ns speed grade.

Does the 71V67703S85BQ support both linear and interleaved burst modes?

Yes, the 71V67703S85BQ supports both burst modes via the LBO (Linear/Interleaved Burst Order) pin. When LBO is driven LOW, the device uses linear burst ordering (00→01→10→11); when LBO is HIGH, it uses interleaved ordering (00→01→11→10). LBO is a static DC input and must remain stable during burst operation - changing it mid-burst may cause undefined address sequencing.

How does the 71V67703S85BQ handle partial writes to its 36-bit data bus?

Partial writes are supported through four independent byte-write enables (BW1–BW4), each controlling a 9-bit segment (BW1: I/O0–7 + I/OP1; BW2: I/O8–15 + I/OP2; etc.), gated by the synchronous BWE input. When BWE is LOW and a specific BWx is LOW on the rising CLK edge, only that 9-bit byte is written; all other bytes retain their prior values. This eliminates need for read-modify-write cycles.

What is the function of the ZZ pin on the 71V67703S85BQ?

The ZZ pin is an asynchronous sleep mode input. When driven HIGH, the 71V67703S85BQ gates its internal clock and enters full-sleep mode, reducing supply current to ≤70mA (ISB2) while retaining all stored data. ZZ requires no setup/hold timing relative to CLK and can be asserted at any time - including during active burst sequences - with guaranteed data retention.

Is the 71V67703S85BQ compatible with 5V-tolerant systems?

No, the 71V67703S85BQ is strictly a 3.3V device: VDD and VDDQ are specified at 3.3V ±5% (3.135V–3.465V). Input voltage limits are VIH = 2.0V min (VDD+0.3V max) and VIL = –0.3V min (0.8V max), confirming incompatibility with 5V logic levels. Interfacing with 5V systems requires level-shifting circuitry on all address, control, and data lines.