Renesas 71V2546S133BGI8

Overview

71V2546S133BGI8 from IDT is a 128K × 36-bit (4.5 Mbit), 3.3V synchronous ZBT™ SRAM with 2.5V I/O, pipelined outputs, and zero-bus-turnaround architecture. It delivers 133 MHz operation (7.5 ns clock-to-data access), supports 4-word linear/interleaved burst modes via internal counter, and features individual byte write control (BW1–BW4) for precise data manipulation in high-speed networking and packet buffering applications.

For engineers reviewing the 71V2546S133BGI8 datasheet, 71V2546S133BGI8 pinout, 71V2546S133BGI8 application, or 71V2546S133BGI8 equivalent, key selection criteria include its ZBT™ timing behavior (no dead cycles between read/write transitions), 100-pin TQFP industrial-grade packaging (–40°C to +85°C), and dual-supply operation (3.3V core / 2.5V I/O) enabling compatibility with modern low-voltage logic interfaces.

Technical Context

This SRAM implements fully synchronous, positive-edge-triggered registers for address, control, and data signals-enabling full pipelining with deterministic two-cycle latency from address/control registration to data output. Its on-chip burst counter, controlled by ADV/LD and LBO pins, generates sequential addresses internally during burst reads/writes without external sequencing logic.

The device uses three independent chip enables (CE1, CE2, CE2) for flexible depth expansion and supports suspended operation via Clock Enable (CEN), holding all internal register states when asserted. Output enable (OE) is asynchronous but internally synchronized to eliminate timing hazards, and the ZBT™ architecture eliminates bus turnaround delays by overlapping write completion and read initiation within the same cycle boundary.

Key Specifications

Pinout & Package

Packaged in a JEDEC-standard 100-pin plastic thin quad flatpack (TQFP), the 71V2546S133BGI8 provides 36 bidirectional data I/Os (I/O0–I/O31, I/OP1–I/OP4), 17 address inputs (A0–A16), and dedicated control pins including CLK, R/W, CEN, OE, ADV/LD, LBO, and four byte-write enables (BW1–BW4).

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1315KV18-133BZI and AS7C31026B-133BIN, the 71V2546S133BGI8 uniquely delivers 36-bit width, true ZBT™ timing, and integrated burst counter-making it irreplaceable for high-efficiency packet buffering where bus utilization and deterministic latency are design-critical.

Availability

71V2546S133BGI8 is available at Aetrix Electronics and suitable for high-speed packet buffering, network switch fabric memory, and telecom line card applications requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 71V2546S133BGI8 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 71V2546S133BGI8 belongs to IDT's ZBT™ SRAM product line, engineered specifically for zero-latency bus turnaround in packet-switched networks, telecom equipment, and real-time embedded systems demanding deterministic memory access.

FAQ

What is the maximum operating frequency of the 71V2546S133BGI8?

The 71V2546S133BGI8 is rated for a maximum clock frequency of 133 MHz, corresponding to a 7.5 ns clock-to-data access time. This specification is guaranteed across the full industrial temperature range (–40°C to +85°C) and under nominal 3.3V ±5% VDD and 2.5V ±5% VDDQ supply conditions, as verified in the official IDT datasheet revision 6.42.

Does the 71V2546S133BGI8 support both linear and interleaved burst modes?

Yes, the 71V2546S133BGI8 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) and to VDD for interleaved (0,2,1,3). This configuration is sampled at the start of each burst cycle and determines the internal address counter progression without software involvement.

How does the ZBTTM architecture in the 71V2546S133BGI8 eliminate bus dead cycles?

The ZBTTM (Zero Bus Turnaround) architecture in the 71V2546S133BGI8 allows immediate transition from a write cycle to a read cycle-or vice versa-without inserting idle clock cycles. By overlapping the final data capture of one operation with the initial address sampling of the next, it maintains continuous bus activity, achieving near-100% utilization in burst-intensive applications like packet buffering.

What are the voltage requirements for VDD and VDDQ on the 71V2546S133BGI8?

The 71V2546S133BGI8 requires VDD = 3.3 V ±5% for core logic operation and VDDQ = 2.5 V ±5% for I/O interface levels. These supplies must be independently regulated; VDDQ must not exceed VDD, and input pins referenced to VDDQ (e.g., I/Os, BWx) must remain within –0.5 V to VDDQ + 0.5 V per absolute maximum ratings.

Is the 71V2546S133BGI8 available in an industrial temperature grade?

Yes, the 71V2546S133BGI8 is specified for industrial temperature operation from –40°C to +85°C. This rating is confirmed in the "Recommended Operating Temperature and Supply Voltage" table of the IDT datasheet (revision 6.42), and the 'BGI8' suffix explicitly denotes the industrial-grade 100-pin TQFP package variant.