Renesas 71V65703S85BG8

Overview

71V65703S85BG8 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. It serves as high-speed buffer or cache memory in network packet processors, telecom line cards, and FPGA co-processor interfaces requiring deterministic burst latency.

For engineers reviewing the 71V65703S85BG8 datasheet, 71V65703S85BG8 pinout, 71V65703S85BG8 application, or 71V65703S85BG8 equivalent, key selection criteria include ZBT™ burst timing compliance, 3.3V I/O compatibility with VDDQ decoupling, industrial temperature support (–40°C to +85°C), and TQFP-100 package footprint for legacy board reuse.

Technical Context

The 71V65703S85BG8 implements a synchronous, clocked architecture with registered address/control inputs and flow-through data outputs-no output register-enabling predictable 1-cycle data valid timing after CLK edge. Its on-chip 4-word burst counter supports both linear and interleaved sequences via LBO pin control, and internally synchronized OE eliminates external timing coordination.

ZBTTM functionality is achieved through dedicated ADV/LD and R/W sequencing: write-to-read or read-to-write transitions occur without dead cycles by advancing the burst counter on rising CLK while maintaining bus ownership. Three chip enables (CE1, CE2 active-low; CE2 active-high) enable depth expansion with one-cycle deselect and tri-state hold.

Key Specifications

Pinout & Package

71V65703S85BG8 is packaged in a 100-pin plastic thin quad flatpack (TQFP), JEDEC MO-140AC, 14 mm × 20 mm body, 0.5 mm pitch. Pin 1 marked by dot; top-side marking includes "71V65703S85BG8" and date code.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1355BV33-100AXC and AS7C3256B-10JIN, the 71V65703S85BG8 uniquely delivers flow-through outputs with ZBTTM burst sequencing - enabling true zero-cycle turnaround in high-frequency packet buffering and real-time control loops where deterministic latency is non-negotiable.

Availability

71V65703S85BG8 is available at Aetrix Electronics and suitable for telecom infrastructure, industrial automation, and FPGA-accelerated computing applications requiring stable component supply, long-lifecycle support, and industrial temperature qualification.

Supply support for 71V65703S85BG8 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 fabless semiconductor company specializing in high-performance timing, memory, and interface solutions for communications and computing markets.

The 71V65703S85BG8 belongs to IDT's ZBT™ SRAM product line, engineered specifically for zero-bus-turnaround applications in network switches, routers, and baseband processing units demanding sub-10 ns latency and burst efficiency.

FAQ

What is the memory organization of the 71V65703S85BG8?

The 71V65703S85BG8 is strictly configured as 256K × 36 (9,437,184 bits). Unlike the family's dual-configuration variants (e.g., 71V65903), this specific part does not support 512K × 18 mode - its address bus is fixed to A0–A17 and data bus to 36 bits (I/O0–I/O31 + I/OP1–I/OP4).

Does the 71V65703S85BG8 support both linear and interleaved burst modes?

Yes, the 71V65703S85BG8 supports both burst orders via the LBO pin: LBO = LOW selects linear sequence (A0, A0+1, A0+2, A0+3), and LBO = HIGH selects interleaved (A0, A0+2, A0+1, A0+3). This selection is static and must be held stable during burst operation.

How does the 71V65703S85BG8 achieve zero bus turnaround?

The 71V65703S85BG8 achieves ZBTTM by using ADV/LD to control burst counter advancement independently of R/W state. When transitioning from write to read (or vice versa), ADV/LD remains HIGH to increment the counter while R/W toggles - eliminating idle bus cycles required by conventional SRAMs.

What is the role of the three chip enable pins (CE1, CE2, CE2) on the 71V65703S85BG8?

CE1 and CE2 are active-low enables; CE2 is active-high. The device is selected only when CE1 = LOW, CE2 = LOW, and CE2 = HIGH. Any deviation initiates a 1-cycle deselect - tri-stating the data bus on the next CLK edge - enabling clean depth expansion without external glue logic.

Can the 71V65703S85BG8 operate in low-power sleep mode, and how is it controlled?

Yes, the 71V65703S85BG8 supports sleep mode via the asynchronous ZZ pin. When ZZ = HIGH, internal clock gating reduces active current to ~100 µA while guaranteeing full data retention - ideal for intermittent operation in battery-backed or thermally constrained systems.