Renesas 71V546S133PFGI8

Overview

71V546S133PFGI8 from Integrated Device Technology is a 3.3V, 128K × 36-bit (4.5 Mbit) synchronous SRAM with Zero Bus Turnaround (ZBT™) architecture, pipelined outputs, and 4-word burst capability. It operates at 133 MHz (7.5 ns cycle time), delivers 4.2 ns clock-to-data access, and supports linear or interleaved burst ordering via LBO pin. It is used in high-speed packet buffering and network switch fabric control planes.

For engineers reviewing the 71V546S133PFGI8 datasheet, 71V546S133PFGI8 pinout, 71V546S133PFGI8 application, or 71V546S133PFGI8 equivalent, key selection criteria include ZBT™ bus turnaround elimination, synchronous 3.3V operation with CEN/ADV/LD control logic, JEDEC-standard 100-pin TQFP packaging, and industrial temperature support (–40°C to +85°C).

Technical Context

The 71V546S133PFGI8 implements a fully pipelined synchronous interface with address/control registration on the rising CLK edge and data output registration two cycles later. Its ZBT™ architecture eliminates dead cycles between read/write transitions by decoupling bus direction control from memory access timing.

It integrates an on-chip 4-word burst counter, selectable via ADV/LD and LBO pins, and supports individual byte write (BW1–BW4) for 9-bit granularity. Three chip enables (CE1, CE2, CE2) enable depth expansion while maintaining deterministic two-cycle deselect behavior.

Key Specifications

Pinout & Package

Packaged in a JEDEC-standard 100-pin thin quad flatpack (TQFP), 14 mm × 20 mm body, lead-free and RoHS-compliant (PFGI8 suffix denotes industrial temp, green package).

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1355BV18-133BZI and AS7C3256A-133JCIN, the 71V546S133PFGI8 uniquely delivers ZBT™-enabled bus efficiency, synchronous burst addressing, and industrial-temperature reliability in a single 100-pin TQFP package-making it optimal for real-time packet processing where deterministic latency and bus utilization matter.

Availability

71V546S133PFGI8 is available at Aetrix Electronics and suitable for high-speed packet buffering, telecom line card control memory, and industrial PLC communication modules requiring stable component supply across extended temperature ranges.

Supply support for 71V546S133PFGI8 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

Integrated Device Technology (IDT), now part of Renesas Electronics, is a fabless semiconductor company specializing in timing, memory interface, RF, and high-performance interconnect solutions.

The IDT71V546 product line was designed specifically for high-bandwidth, low-latency buffering in networking and telecom infrastructure-emphasizing ZBT™ architecture, burst efficiency, and industrial reliability.

FAQ

What is the maximum operating frequency of the 71V546S133PFGI8?

The 71V546S133PFGI8 is rated for a maximum clock frequency of 133 MHz, corresponding to a 7.5 ns minimum clock cycle time (tCYC). This specification is guaranteed over the full industrial temperature range (–40°C to +85°C) and 3.3 V ±5% supply voltage. The device achieves 4.2 ns clock-to-data access (tCD) at this speed, making it suitable for demanding high-throughput buffering applications. Performance is validated per AC Electrical Characteristics Table 23 in the official datasheet.

Does the 71V546S133PFGI8 support burst read and write operations?

Yes, the 71V546S133PFGI8 supports 4-word burst operations for both reads and writes. Burst mode is initiated by sampling ADV/LD = HIGH after loading an initial address, and the sequence order (linear or interleaved) is selected via the LBO pin. Each burst delivers four consecutive 36-bit words using a single base address, reducing address bus activity and improving effective bandwidth. Burst behavior is fully synchronous and deterministic, with data appearing two cycles after the corresponding control signal.

What is the function of the three chip enable pins (CE1, CE2, CE2) on the 71V546S133PFGI8?

The 71V546S133PFGI8 uses CE1 and CE2 as active-low chip enables and CE2 as an active-high chip enable. All three must be asserted (CE1 = LOW, CE2 = LOW, CE2 = HIGH) to select the device. This triple-enable scheme allows flexible depth expansion across multiple SRAMs using simple logic combinations-e.g., decoding higher-order address bits to drive CE lines. Deselection initiates a deterministic two-cycle shutdown, tri-stating outputs cleanly without bus contention.

How does the ZBTTM feature eliminate bus turnaround cycles in the 71V546S133PFGI8?

The ZBTTM (Zero Bus Turnaround) feature in the 71V546S133PFGI8 removes idle cycles between alternating read and write operations by decoupling bus direction control from memory access timing. Unlike conventional SRAMs that require explicit OE or direction control overhead, the 71V546S133PFGI8 uses synchronous R/W and pipelined registers to ensure continuous data flow-even on read-after-write transitions. This enables full utilization of the data bus in high-speed packet processing and switch fabric applications.

Is the 71V546S133PFGI8 pin-compatible with other members of the IDT71V546 family?

Yes, the 71V546S133PFGI8 shares identical pinout and package (100-pin TQFP) with other speed grades in the IDT71V546 family, including the 100 MHz 71V546S100PFGI8. All variants use the same footprint, signal assignments, and power/ground pin layout. However, timing parameters (e.g., tCD, tCYC) differ by speed grade, so PCB design and timing closure must align with the specific variant's AC characteristics. No layout changes are required for drop-in replacement within the same package option.