Renesas 71V546S100PFGI

Overview

71V546S100PFGI from Integrated Device Technology is a 128K × 36-bit, 4.5 Mbit, 3.3V synchronous SRAM with ZBT™ (Zero Bus Turnaround) architecture, pipelined outputs, and 4-word burst capability. It operates at 100 MHz (10 ns clock cycle), delivers 4.2 ns clock-to-data access in read mode, and supports interleaved or linear burst ordering via the LBO pin. It is used in high-speed packet buffering and network switch fabric control planes where bus turnaround latency must be eliminated.

For engineers reviewing the 71V546S100PFGI datasheet, 71V546S100PFGI pinout, 71V546S100PFGI application, or 71V546S100PFGI equivalent, key selection criteria include its 100-pin TQFP package, synchronous R/W control with ADV/LD-driven burst counter, individual byte write enables (BW1–BW4), and industrial temperature support (–40°C to +85°C).

Technical Context

The 71V546S100PFGI implements a fully pipelined synchronous interface with all address, control, and data registers triggered on the positive clock edge. Its ZBT™ architecture eliminates dead cycles between consecutive read/write operations by decoupling address load and data transfer timing-data appears two clocks after address/control registration.

It integrates an on-chip burst counter and supports both linear and interleaved 4-word burst sequences selected by the static LBO pin. The device uses three chip enables (CE1, CE2 low-active; CE2 high-active) for flexible depth expansion and features registered I/O paths with asynchronous OE for output tri-state control independent of clock timing.

Key Specifications

Pinout & Package

71V546S100PFGI is packaged in a JEDEC-standard 100-pin thin quad flatpack (TQFP), 14 mm × 20 mm body size, with 0.5 mm lead pitch and exposed pad not present. Pin 1 is marked by corner notch; pin 14 is NC but requires VIH > 2.0 V if left unconnected.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1355BV18-100BZI and AS7C3256A-10JIN, the 71V546S100PFGI uniquely delivers ZBT™-enabled zero-turnaround operation and integrated burst sequencing in a drop-in 100-pin TQFP package-critical for latency-constrained networking and real-time control systems.

Availability

71V546S100PFGI is available at Aetrix Electronics and suitable for network packet buffering, telecom switch fabric control, and industrial PLC data logging requiring stable component supply and long-term industrial temperature support.

Supply support for 71V546S100PFGI 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, computing, and industrial markets.

The IDT71V546 product line was designed specifically for high-performance, low-latency synchronous memory applications in networking equipment and real-time embedded systems where bus turnaround overhead must be eliminated.

FAQ

What does the 'S100' suffix in 71V546S100PFGI indicate?

The 'S100' suffix denotes the speed grade: 100 MHz maximum clock frequency (tCYC = 10 ns). This is confirmed in the AC Electrical Characteristics table, where 71V546S100 specifies tCYC = 10 ns (min) and fMAX = 100 MHz. The 71V546S100PFGI is functionally identical to other S100 variants but qualified in the industrial temperature range (–40°C to +85°C) and packaged in a 100-pin TQFP.

Does 71V546S100PFGI support true ZBT™ (Zero Bus Turnaround) operation?

Yes, the 71V546S100PFGI implements true ZBT™ operation as defined by IDT: it eliminates dead cycles between consecutive read and write operations. The datasheet explicitly states that "no dead cycles between write and read cycles" are required, and timing waveforms confirm back-to-back R/W transitions with no bus idle period-verified in the Synchronous Truth Table and Combined Read/Write Timing Diagram (Figure 3821 drw 08).

How is burst addressing controlled on the 71V546S100PFGI?

Burst addressing is controlled by the ADV/LD and LBO pins. When ADV/LD is sampled HIGH on the rising clock edge, the internal burst counter advances; when sampled LOW, a new external address is loaded. LBO selects burst order: LOW for linear (0,1,2,3), HIGH for interleaved (0,2,1,3). This behavior is documented in the Pin Definitions table (3821 tbl 02) and Burst Sequence Tables (3821 tbl 09–10).

Can the 71V546S100PFGI operate with only two chip enables?

Yes-the 71V546S100PFGI requires CE1 = LOW, CE2 = LOW, and CE2 = HIGH to assert selection. CE2 is active-high and functionally complementary to CE1/CE2; all three must be asserted simultaneously. The datasheet states "to select the chip requires CE1 = L, CE2 = L, CE2 = H" (3821 tbl 07, Note 5), confirming that all three enables are mandatory for normal operation.

What is the role of the I/OP1–I/OP4 pins on the 71V546S100PFGI?

The I/OP1–I/OP4 pins are 4 dedicated parity bits associated with the 32-bit data bus (I/O0–I/O31), forming a full 36-bit interface. They support error detection in mission-critical applications. The Functional Block Diagram (3821 drw 01) and Pin Description Summary (3821 tbl 01) explicitly list them as "Data Input/Output" with P1–P4 designation, and the memory organization is defined as 128K × 36 in the title and description.