Renesas 71V2546S133PFG8

Overview

71V2546S133PFG8 from IDT (now Renesas) is a 3.3V, 128K × 36-bit synchronous ZBT™ SRAM with pipelined outputs, 133 MHz operation (7.5 ns clock-to-data), 2.5V I/O supply, and zero bus turnaround architecture. It features four-word burst capability (linear or interleaved), individual byte write control (BW1–BW4), and three chip enables for depth expansion - deployed in high-speed packet buffering and network switch data planes.

For engineers reviewing the 71V2546S133PFG8 datasheet, 71V2546S133PFG8 pinout, 71V2546S133PFG8 application, or 71V2546S133PFG8 equivalent, key selection criteria include its ZBT timing behavior, 100-pin TQFP package compatibility, industrial temperature support (–40°C to +85°C), and strict 3.3V core / 2.5V I/O voltage separation.

Technical Context

This SRAM implements fully synchronous, positive-edge-triggered registers for address, control, and data paths, enabling full pipelining with two-cycle latency from address/control registration to data output. Its internal burst counter and LBO-controlled linear/interleaved addressing eliminate external sequencing logic.

The device uses three independent chip enables (CE1, CE2, CE2) with hierarchical deselection logic, Clock Enable (CEN) for cycle suspension, and internally synchronized OE to remove timing constraints on output enable assertion - all supporting deterministic, dead-cycle-free read/write transitions.

Key Specifications

Pinout & Package

Packaged in JEDEC-standard 100-pin plastic thin quad flatpack (TQFP), 14 mm × 20 mm body, 0.5 mm pitch. Pin 1 marked by dot; top-side marking includes "71V2546S133PFG8" and date code.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1315KV18-133BZI and AS7C31026B-133JCIN, the 71V2546S133PFG8 uniquely delivers 36-bit width, true ZBT timing, and LBO-selectable burst ordering in a drop-in 100-pin TQFP - making it irreplaceable for legacy high-speed networking designs requiring minimal layout change.

Availability

71V2546S133PFG8 is available at Aetrix Electronics and suitable for network switch buffering, telecom line card memory, and industrial real-time controller cache applications requiring stable component supply across extended product lifecycles.

Supply support for 71V2546S133PFG8 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 71V2546S133PFG8 belongs to IDT's ZBT SRAM product line, engineered specifically for zero-latency, high-throughput data buffering in packet-switched networks and telecom systems where deterministic burst access is mandatory.

FAQ

What is the maximum operating frequency of the 71V2546S133PFG8?

The 71V2546S133PFG8 is rated for 133 MHz operation, corresponding to a 7.5 ns clock period and guaranteed 7.5 ns clock-to-data access time under commercial and industrial temperature conditions. This frequency is validated with VDD = 3.3 V ±5% and VDDQ = 2.5 V, and assumes proper signal integrity and termination per the datasheet AC test conditions.

Does the 71V2546S133PFG8 support true ZBT™ (Zero Bus Turnaround) operation?

Yes, the 71V2546S133PFG8 implements true ZBT™ architecture: it eliminates dead cycles between consecutive read and write bursts by overlapping bus turnaround with the next address setup. This behavior is intrinsic to its internal control logic and requires no external sequencing - confirmed in the functional description, truth tables, and timing diagrams of the official datasheet.

What package type and pin count does the 71V2546S133PFG8 use?

The 71V2546S133PFG8 is supplied exclusively in a 100-pin plastic thin quad flatpack (TQFP) per JEDEC MO-145, with 0.5 mm pitch and 14 mm × 20 mm body size. The "PFG8" suffix explicitly denotes this TQFP package; no BGA variant carries the same full part number.

Can the 71V2546S133PFG8 operate with only a 3.3V supply, or is the 2.5V I/O supply mandatory?

The 2.5V I/O supply (VDDQ) is mandatory for correct operation of the 71V2546S133PFG8. The device uses separate 3.3V (VDD) for core logic and 2.5V (VDDQ) for I/O drivers/receivers. Operating VDDQ outside 2.2V–2.7V violates absolute maximum ratings and will cause I/O level incompatibility or functional failure - as specified in the Recommended DC Operating Conditions table.

How does burst addressing work on the 71V2546S133PFG8, and what controls the sequence order?

Burst addressing on the 71V2546S133PFG8 is controlled by the LBO (Linear/Interleaved Burst Order) pin: tied to VSS for linear order (A0, A1, A2, A3) or VDD for interleaved order (A0, A2, A1, A3). The internal burst counter advances on ADV/LD = HIGH, and the full 4-word sequence is generated from a single loaded base address - eliminating need for external address generation logic.