Renesas 71V546S100PFG

Overview

71V546S100PFG from Integrated Device Technology is a 3.3V, 128K × 36-bit synchronous SRAM with Zero Bus Turnaround (ZBT™) architecture, pipelined outputs, and 4-word burst capability. It delivers 100 MHz operation (10 ns clock cycle), 5 ns clock-to-data access, and supports linear or interleaved burst ordering via the LBO pin. It is used in high-speed packet buffering and network switch fabric control planes where zero-cycle bus turnaround between read/write operations is critical.

For engineers reviewing the 71V546S100PFG datasheet, 71V546S100PFG pinout, 71V546S100PFG application, or 71V546S100PFG equivalent, key selection criteria include ZBT™ timing compliance, 100-pin TQFP mechanical compatibility, 3.3V ±5% supply tolerance, industrial temperature support (–40°C to +85°C), and burst-mode byte-write granularity across four 9-bit I/O groups.

Technical Context

The 71V546S100PFG implements a fully synchronous, clock-edge-triggered architecture with registered address, control, and data paths. All inputs except OE are sampled on the rising CLK edge, and data output appears two cycles later-enabling deterministic pipeline timing for back-to-back memory accesses.

Its ZBT™ feature eliminates dead cycles during bus direction reversal by decoupling write completion from read initiation using internal burst counters and ADV/LD-controlled address loading. The device supports individual byte write enables (BW1–BW4), three chip enables (CE1, CE2, CE2) with mixed polarity, and static LBO configuration for burst sequence selection.

Key Specifications

Pinout & Package

Packaged in a JEDEC-standard 100-pin thin quad flatpack (TQFP), the 71V546S100PFG features a 14 mm × 20 mm body with 0.5 mm pitch leads. Pin 1 is marked by a corner notch; pin 14 is a no-connect (NC) but may be tied to VDD if required per design margining.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1371DV33-100AXC and AS7C3128B-10JCN, the 71V546S100PFG uniquely delivers zero-bus-turnaround timing within a standard synchronous SRAM interface-enabling simpler controller design and higher effective throughput in burst-intensive applications like packet switching and real-time buffering.

Availability

71V546S100PFG is available at Aetrix Electronics and suitable for network packet buffering, telecom line card control, and industrial PLC data logging requiring stable component supply across extended product lifecycles.

Supply support for 71V546S100PFG 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 power management ICs for communications and computing infrastructure.

The IDT71V546 product line was designed specifically for high-speed, low-latency data buffering in networking and telecom equipment-emphasizing ZBT™ timing, burst efficiency, and industrial reliability.

FAQ

What is the maximum operating frequency of the 71V546S100PFG?

The 71V546S100PFG is rated for 100 MHz operation, corresponding to a minimum clock cycle time (tCYC) of 10 ns. This frequency is guaranteed across the full industrial temperature range (–40°C to +85°C) and 3.3V ±5% supply voltage. Performance validation includes tCD ≤ 5 ns and tCL/tCH ≥ 3.5 ns, ensuring reliable timing margin in high-speed synchronous systems. The 71V546S100PFG achieves this without requiring special cooling or voltage derating.

Does the 71V546S100PFG support true ZBT™ (Zero Bus Turnaround) behavior?

Yes, the 71V546S100PFG implements genuine ZBT™ functionality: a write cycle can be immediately followed by a read cycle-or vice versa-without inserting idle bus cycles. This is achieved through internal pipelining, registered outputs, and the ADV/LD-controlled burst counter, which allows the bus direction to reverse in one clock cycle. The 71V546S100PFG datasheet confirms zero dead cycles between consecutive read/write operations under valid timing conditions.

How does the LBO pin affect burst addressing in the 71V546S100PFG?

The LBO (Linear Burst Order) pin configures the 71V546S100PFG's 4-word burst sequence: when LBO = LOW, the device uses linear addressing (A0, A1, A2, A3); when LBO = HIGH, it uses interleaved order (A0, A2, A1, A3). This selection is static and must be set before burst initiation. The 71V546S100PFG internally pulls LBO to VDD if left unconnected, defaulting to interleaved mode-critical for cache-line-aligned memory access patterns.

Can the 71V546S100PFG operate with only two chip enables active?

No-the 71V546S100PFG requires all three chip enables to be asserted simultaneously for device selection: CE1 = LOW, CE2 = LOW, and CE2 = HIGH. If any one is violated (e.g., CE2 = LOW), the device enters deselect mode, tri-stating outputs after two clock cycles. This three-signal scheme enables precise depth expansion control and avoids partial enable states that could cause bus contention. The 71V546S100PFG truth table explicitly defines this logical condition for chip selection.

What is the function of the ADV/LD pin during normal read and write operations in the 71V546S100PFG?

In the 71V546S100PFG, ADV/LD serves dual roles: when sampled LOW at the rising CLK edge, it loads a new external address into the internal register (initiating a load cycle); when sampled HIGH, it advances the internal burst counter (enabling burst mode). During burst reads/writes, R/W is ignored-only its state at the initial load cycle determines access type. This behavior is confirmed in the 71V546S100PFG synchronous truth table and timing waveforms, ensuring deterministic address sequencing.