Renesas 71V2556SA100BGG

Overview

71V2556SA100BGG from IDT (now Renesas) is a 3.3V synchronous ZBT™ SRAM with 128K × 36-bit (4.5 Mbit) organization, 100 MHz operation (10 ns clock-to-data), pipelined outputs, and zero-bus-turnaround architecture. It supports 4-word linear/interleaved burst, individual byte write control (BW1–BW4), and operates across industrial temperature (–40°C to +85°C) in JEDEC-standard 100-pin TQFP packaging. Used in high-speed packet buffering and network switch data planes.

For engineers reviewing the 71V2556SA100BGG datasheet, 71V2556SA100BGG pinout, 71V2556SA100BGG application, or 71V2556SA100BGG equivalent, key selection criteria include ZBT timing compliance, 2.5V I/O voltage compatibility, TQFP-100 mechanical fit, burst counter behavior under ADV/LD control, and JTAG testability support in SA variants.

Technical Context

The 71V2556SA100BGG implements a fully synchronous, clock-edge-triggered architecture with input registers for address, control, and data, plus output registers for pipelined reads. Its internal burst counter advances on ADV/LD = HIGH and loads external addresses on ADV/LD = LOW, enabling deterministic 4-word burst sequences selected by LBO pin state.

ZBT functionality eliminates dead cycles between read/write transitions via internally synchronized OE and dual-phase bus control logic. The device integrates three chip enables (CE1, CE2, CE2) for depth expansion and supports optional IEEE 1149.1 JTAG boundary scan-enabled only in SA versions with dedicated TMS/TDI/TCK/TDO/TRST pins.

Key Specifications

Pinout & Package

Packaged in JEDEC-standard 100-pin thin quad flatpack (TQFP), 14 mm × 20 mm body, 0.5 mm pitch. Pin 1 marked by corner notch; top-view orientation per datasheet drawing 4875 drw 02.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1356BV100BZC and AS7C3256A-10TIN, the 71V2556SA100BGG uniquely delivers zero-bus-turnaround timing, integrated burst sequencing, and JTAG testability in a 36-bit TQFP package - making it optimal for deterministic, high-throughput packet buffering where bus efficiency and test coverage are critical.

Availability

71V2556SA100BGG is available at Aetrix Electronics and suitable for network switch buffering, telecom line card memory, industrial PLC data logging, and ATE pattern memory requiring stable component supply and long-term industrial temperature support.

Supply support for 71V2556SA100BGG 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 infrastructure.

The 71V2556SA100BGG belongs to IDT's ZBT SRAM product line, designed specifically for low-latency, high-throughput data buffering in networking, telecom, and test equipment where deterministic bus turnaround and burst efficiency are essential.

FAQ

What does the "SA" suffix indicate in 71V2556SA100BGG?

The "SA" suffix denotes the version with optional IEEE 1149.1 JTAG boundary scan capability. Unlike base "S" variants, the 71V2556SA100BGG includes dedicated TMS, TDI, TCK, TDO, and TRST pins routed to the 100-pin TQFP package, enabling in-system testability without requiring external test adapters or additional circuitry.

Does 71V2556SA100BGG support both linear and interleaved burst modes?

Yes, the 71V2556SA100BGG supports both linear and interleaved 4-word burst sequences. The LBO (Linear/Interleaved Burst Order) pin selects the mode: tied to VSS for linear (0,1,2,3) or to VDD for interleaved (0,2,1,3). This flexibility allows alignment with specific ASIC or FPGA memory controller addressing schemes without firmware changes.

How is the 36-bit data width implemented on 71V2556SA100BGG?

The 71V2556SA100BGG implements its 36-bit width as 32 data bits (I/O0–I/O31) plus 4 parity bits (I/OP1–I/OP4). All 36 bits are accessed simultaneously during read/write cycles. Byte write enables (BW1–BW4) each control one 9-bit segment: BW1→I/O0–I/O8+I/OP1, BW2→I/O9–I/O17+I/OP2, etc., preserving ECC integrity per subword.

What is the role of the ADV/LD pin in 71V2556SA100BGG operation?

The ADV/LD pin serves a dual function: when LOW, it loads a new external address into the internal address register; when HIGH, it increments the on-chip burst counter. This eliminates need for external address sequencing logic and enables fully self-contained 4-word bursts - critical for reducing controller overhead in high-speed packet processing applications using the 71V2556SA100BGG.

Can 71V2556SA100BGG operate reliably at 100 MHz across the full industrial temperature range?

Yes, the 71V2556SA100BGG is fully characterized and guaranteed to operate at 100 MHz (10 ns clock period) from –40°C to +85°C with 3.3V ±5% VDD and 2.5V ±0.2V VDDQ. AC timing parameters including tCD (clock-to-data), tCO (output hold), and tSU/tH (setup/hold) are specified across this range, ensuring deterministic timing closure in thermally demanding industrial deployments.