Renesas 71V65703S85BQ8

Overview

71V65703S85BQ8 from IDT (now Renesas) is a 3.3V synchronous ZBT™ SRAM organized as 256K × 36 (9,437,184-bit), supporting 100 MHz operation with 7.5 ns clock-to-data access, zero bus turnaround between read/write cycles, and flow-through outputs for high-speed burst data transfer in networking and telecom buffer applications.

For engineers reviewing the 71V65703S85BQ8 datasheet, 71V65703S85BQ8 pinout, 71V65703S85BQ8 application, or 71V65703S85BQ8 equivalent, key selection criteria include its 100-pin TQFP package, 4-word interleaved/linear burst capability, individual byte write control (BW1–BW4), synchronous R/W and ADV/LD interface, and industrial temperature support (–40°C to +85°C).

Technical Context

The 71V65703S85BQ8 implements a synchronous dual-edge-triggered architecture with an on-chip burst counter and flow-through output path-no output register-enabling deterministic 1-cycle latency from address/control assertion to data availability. Its ZBT™ architecture eliminates dead cycles by allowing immediate bus direction reversal after any access.

It uses three chip enables (CE1, CE2 active-low; CE2 active-high) for depth expansion, supports asynchronous OE and ZZ (sleep mode), and features internally synchronized output buffer enable-removing external OE timing constraints. The LBO pin statically selects linear or interleaved burst order, and CEN suspends all synchronous operation without affecting output state.

Key Specifications

Pinout & Package

71V65703S85BQ8 is packaged in a JEDEC-standard 100-pin TQFP (PKG100), 14 mm × 20 mm body, with exposed thermal pad option per datasheet revision. Pin functions are fully defined for 256K × 36 configuration; unused pins (e.g., A18, NC positions) are no-connects in this variant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1362BV33-100AXC and AS7C3256B-10JIN, the 71V65703S85BQ8 uniquely balances deterministic 7.5 ns access, zero-turnaround burst efficiency, and simple single-clock synchronous control-making it optimal for cost-sensitive, high-throughput telecom buffers where QDR complexity or async overhead is prohibitive.

Availability

71V65703S85BQ8 is available at Aetrix Electronics and suitable for packet buffering, telecom line cards, backplane interface buffers, and high-speed test equipment requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 71V65703S85BQ8 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 leader specializing in high-performance timing, memory interface, and RF solutions for communications and computing infrastructure.

The 71V65703S85BQ8 belongs to IDT's ZBT™ SRAM product line, designed specifically for low-latency, high-bandwidth buffering in networking ASICs, telecom line cards, and test instrumentation where deterministic timing and burst efficiency are critical.

FAQ

What is the memory organization and total capacity of the 71V65703S85BQ8?

The 71V65703S85BQ8 is organized as 256K × 36, delivering 9,437,184 bits (9.4 Mbit) of synchronous SRAM. It is pin-compatible with the 512K × 18 variant (71V65903), but the 71V65703S85BQ8 specifically implements the 256K × 36 configuration with A0–A17 address lines active and A18 unused.

Does the 71V65703S85BQ8 support burst read and write operations-and how is burst order controlled?

Yes, the 71V65703S85BQ8 supports 4-word burst operations in both read and write modes. Burst order is selected via the LBO (Linear/Interleaved Burst Order) pin: LBO = LOW enables linear burst (A0, A1, A2, A3), while LBO = HIGH enables interleaved burst (A0, A2, A1, A3). This is configured statically and must remain stable during operation.

What is the role of the ADV/LD pin in the 71V65703S85BQ8, and how does it interact with burst mode?

The ADV/LD pin determines whether the 71V65703S85BQ8 loads a new external address (ADV/LD = LOW) or advances the internal burst counter (ADV/LD = HIGH). During burst sequences, ADV/LD remains HIGH to auto-increment the address, eliminating the need for external address updates-reducing control overhead in streaming applications.

How does the 71V65703S85BQ8 implement zero bus turnaround (ZBT™), and what design benefit does it provide?

The 71V65703S85BQ8 achieves ZBT™ by allowing immediate bus direction reversal between successive read and write cycles-no dead cycles are inserted. This is enabled by its synchronous control architecture and flow-through outputs. The result is sustained 100 MHz throughput in mixed-access patterns typical of packet buffering and protocol processing.

Can the 71V65703S85BQ8 operate in low-power mode-and how is it activated?

Yes, the 71V65703S85BQ8 supports low-power sleep mode via the asynchronous ZZ pin. When ZZ is driven HIGH, the internal clock is gated and core power drops significantly while data retention is guaranteed. This feature enables dynamic power management in systems with intermittent traffic bursts.