Renesas 71V3556SA100BGI

Overview

71V3556SA100BGI from IDT (now Renesas) is a 128K × 36-bit, 4.5 Mbit, 3.3V synchronous ZBT™ SRAM with zero bus turnaround, pipelined outputs, and 4-word burst capability. It operates at 166 MHz with 3.5 ns clock-to-data access, supports linear/interleaved burst via LBO pin, and features individual byte write (BW1–BW4), JTAG boundary scan (IEEE 1149.1), and sleep mode (ZZ). It is used in high-speed networking packet buffers and telecom line card data path memory.

For engineers reviewing the 71V3556SA100BGI datasheet, 71V3556SA100BGI pinout, 71V3556SA100BGI application, or 71V3556SA100BGI equivalent, key selection criteria include ZBT™ timing compliance, TQFP-100 package compatibility, 3.3V I/O and core supply requirements, burst counter behavior under ADV/LD control, and JTAG test interface availability for system-level validation.

Technical Context

The 71V3556SA100BGI implements a fully synchronous, positive-edge-triggered architecture with registered address, control, and data paths. Its ZBT™ feature eliminates dead cycles between read/write transitions by decoupling bus direction control from OE-output enable is asynchronous but internally synchronized via clocked output registers.

It integrates a 4-word burst counter driven by ADV/LD and LBO, supporting both linear and interleaved sequences. The device uses three chip enables (CE1, CE2, CE2) with two-cycle deselect timing and includes optional IEEE 1149.1 JTAG for boundary scan testing-available only in BGA variants, not in this TQFP-100 variant.

Key Specifications

Pinout & Package

71V3556SA100BGI is packaged in a 100-pin thin quad flatpack (TQFP), JEDEC MO-145AC, 14 mm × 20 mm body, 0.5 mm pitch. Pin 1 is located at bottom-left corner when notch faces up; top-side marking includes "71V3556SA100BGI" and date code.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1356BV18-167BZI and AS7C33128PFSIG, the 71V3556SA100BGI uniquely delivers ZBT™-enabled continuous bus utilization, 36-bit width matching legacy bus architectures, and industrial temperature support-all in a TQFP package with proven reliability in telecom infrastructure.

Availability

71V3556SA100BGI is available at Aetrix Electronics and suitable for high-speed packet buffering, telecom line card memory, and industrial PLC data logging requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 71V3556SA100BGI 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, computing, and industrial markets.

The 71V3556SA100BGI belongs to IDT's ZBT™ SRAM product line, engineered specifically for zero-latency bus turnaround in high-speed data path applications such as network processors, switch fabric controllers, and real-time signal processing systems.

FAQ

What is the maximum operating frequency of the 71V3556SA100BGI?

The 71V3556SA100BGI is rated for a maximum clock frequency of 166 MHz. This specification is validated under industrial temperature conditions (–40°C to +85°C) and 3.3 V ±5% supply, with timing margins meeting JEDEC TQFP-100 package constraints. At this rate, the device achieves 3.5 ns clock-to-data access, enabling deterministic pipelined operation in high-speed systems.

Does the 71V3556SA100BGI support JTAG boundary scan?

No, the 71V3556SA100BGI in the TQFP-100 package does not implement JTAG boundary scan. While the SA suffix indicates JTAG capability in BGA variants (e.g., BG119 or BQ165), the TQFP-100 pinout omits TMS, TDI, TCK, TDO, and TRST pins-confirmed by the PKG100 pin configuration diagrams. JTAG is physically unavailable on this package variant.

How does the ZBT™ feature eliminate dead cycles in the 71V3556SA100BGI?

The ZBT™ feature in the 71V3556SA100BGI removes bus turnaround delays by decoupling direction control from OE. Unlike conventional SRAMs requiring OE deassertion before changing R/W state, the 71V3556SA100BGI uses internally synchronized output registers-so read-to-write or write-to-read transitions occur without inserting idle cycles, sustaining 100% bus utilization at 166 MHz.

What is the function of the ADV/LD and LBO pins on the 71V3556SA100BGI?

On the 71V3556SA100BGI, ADV/LD controls the burst counter: low loads a new external address, high advances the internal counter. LBO selects burst order-low enables linear sequence (0,1,2,3), high enables interleaved (0,2,3,1). Both signals are sampled synchronously on the rising CLK edge and define how the 4-word burst accesses memory without external address generation.

Can the 71V3556SA100BGI operate with different supply voltages for core and I/O?

Yes-the 71V3556SA100BGI requires separate 3.3 V ±5% supplies: VDD for core logic and VDDQ for I/O drivers. This dual-supply architecture allows independent noise management and voltage optimization. Both rails must be within specification simultaneously; VDDQ must not exceed VDD +0.3 V, and VDD must remain ≥ VDDQ −0.3 V to ensure signal integrity and latch-up immunity.