Renesas 71V3556SA133BQ8

Overview

71V3556SA133BQ8 from IDT (now Renesas) is a 3.3V, 128K × 36-bit synchronous ZBT™ SRAM with zero bus turnaround, 133 MHz operation (7.5 ns clock-to-data), pipelined outputs, and JTAG boundary scan (IEEE 1149.1). It supports interleaved/linear 4-word burst, individual byte write (BW1–BW4), and industrial temperature range (–40°C to +85°C). Used in high-speed network packet buffers and telecom line cards where deterministic latency and bus efficiency are critical.

For engineers reviewing the 71V3556SA133BQ8 datasheet, 71V3556SA133BQ8 pinout, 71V3556SA133BQ8 application, or 71V3556SA133BQ8 equivalent, key selection criteria include ZBT™ timing compliance, TQFP-100 package compatibility, 3.3V I/O tolerance, burst counter control via ADV/LD and LBO, and JTAG testability for production validation.

Technical Context

The 71V3556SA133BQ8 implements a fully synchronous, positive-edge-triggered architecture with registered address, data, and control inputs. Its ZBT™ feature eliminates dead cycles between read/write transitions by overlapping bus direction changes with valid data transfers - enabled by internal synchronization of OE and burst counter logic.

It integrates a 4-word burst counter with selectable linear/interleaved order (LBO pin), three chip enables (CE1, CE2, CE2) for depth expansion, and optional IEEE 1149.1 JTAG boundary scan (TMS/TDI/TCK/TDO/TRST) for in-system test. Sleep mode (ZZ) reduces power while retaining data.

Key Specifications

Pinout & Package

71V3556SA133BQ8 is packaged in a JEDEC-standard 100-pin plastic thin quad flatpack (TQFP), 14 mm × 20 mm body, 0.5 mm pitch. Pin 64 supports ZZ (sleep mode) on latest die revision; pins 14/16/66 tolerate VIH-level input without direct VDD connection.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1356BV18-133BZI and AS7C33128PFSIG, the 71V3556SA133BQ8 uniquely delivers native 36-bit width, ZBT™ timing, and integrated JTAG - making it optimal for telecom infrastructure and test-driven industrial designs where bus efficiency and production validation are non-negotiable.

Availability

71V3556SA133BQ8 is available at Aetrix Electronics and suitable for network packet buffers, telecom line cards, industrial PLC controllers, and radar signal processing systems requiring stable component supply, long-term lifecycle support, and industrial temperature qualification.

Supply support for 71V3556SA133BQ8 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 71V3556SA133BQ8 belongs to IDT's ZBT™ SRAM product line, engineered specifically for high-speed networking, telecom infrastructure, and real-time embedded systems demanding deterministic latency and bus efficiency.

FAQ

What is the memory organization and bus width of the 71V3556SA133BQ8?

The 71V3556SA133BQ8 is configured as 128K × 36-bit, providing a native 36-bit data bus with four 9-bit byte lanes (I/O0–I/O31 plus I/OP1–I/OP4). This organization supports full-word access or granular byte writes using BW1–BW4, and is optimized for systems requiring high throughput without external data-width conversion logic.

Does the 71V3556SA133BQ8 support burst mode, and how is burst order controlled?

Yes, the 71V3556SA133BQ8 supports 4-word burst mode with selectable linear or interleaved sequences. Burst order is controlled by the static LBO pin: tied low for linear (0,1,2,3), high for interleaved (0,2,1,3). The ADV/LD signal advances the internal counter synchronously on each rising CLK edge when sampled high.

What is the role of the ZZ pin on the 71V3556SA133BQ8, and does it retain data in sleep mode?

The ZZ pin is the synchronous sleep mode input on the 71V3556SA133BQ8. When driven high, it gates the internal clock and reduces power consumption to its minimum level while guaranteeing full data retention - critical for industrial and telecom applications requiring low-power standby without data loss.

How does the ZBT™ feature eliminate dead cycles in the 71V3556SA133BQ8?

The ZBT™ (Zero Bus Turnaround) feature in the 71V3556SA133BQ8 eliminates dead cycles by overlapping bus direction changes with valid data transfers. Unlike conventional SRAMs that require idle cycles between read/write transitions, the 71V3556SA133BQ8 uses internally synchronized output enable and burst counter logic to enable immediate back-to-back operations.

Is JTAG boundary scan supported on the 71V3556SA133BQ8, and which pins are used?

Yes, the 71V3556SA133BQ8 includes IEEE 1149.1-compliant JTAG boundary scan. Pins TMS, TDI, TCK, TDO, and optional TRST are dedicated to this function. All JTAG pins have internal pull-ups (TRST pull-up), and the feature is active in the "SA" variant - confirmed by the "SA" suffix in the 71V3556SA133BQ8 part number.