Renesas 71V3557S75PFG8

Overview

71V3557S75PFG8 from Integrated Device Technology is a 128K × 36-bit, 4.5 Mbit synchronous ZBT™ SRAM with 3.3V core/I/O supply, 100 MHz operation (7.5 ns clock-to-data), flow-through outputs, and 4-word burst capability. It supports linear/interleaved burst order via LBO pin and eliminates bus turnaround dead cycles between reads and writes. Used in high-speed networking packet buffers and telecom line-card memory subsystems.

For engineers reviewing the 71V3557S75PFG8 datasheet, 71V3557S75PFG8 pinout, 71V3557S75PFG8 application, or 71V3557S75PFG8 equivalent, key selection criteria include ZBT™ zero-turnaround timing, TQFP-100 packaging, JTAG IEEE 1149.1 support, individual byte write enables (BW1–BW4), and synchronous chip enable architecture with CE1/CE2/CE2 logic.

Technical Context

The 71V3557S75PFG8 implements a synchronous dual-edge-triggered address/control register interface with flow-through output path-no output data register-enabling deterministic 1-cycle read latency after address load. Its internal burst counter advances on ADV/LD = HIGH and loads new addresses on ADV/LD = LOW, with burst sequence controlled by static LBO pin level.

It features three chip enables (CE1, CE2 active-low; CE2 active-high) for depth expansion, Clock Enable (CEN) to suspend all synchronous operations without affecting output state, and optional boundary-scan JTAG (TMS/TDI/TCK/TDO/TRST) compliant with IEEE 1149.1. Sleep mode (ZZ) gates internal clock and reduces power while retaining data.

Key Specifications

Pinout & Package

71V3557S75PFG8 is packaged in a JEDEC-standard 100-pin thin quad flatpack (TQFP), 14 mm × 20 mm body, lead pitch 0.5 mm. Pin 1 marked by dot; top-side marking includes "71V3557S75PFG8" and date code.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1355BV18-100BGXI and AS7C31025B-10JIN, the 71V3557S75PFG8 uniquely delivers 36-bit width with ZBT™ zero-turnaround, selectable burst order, and integrated JTAG - making it optimal for next-generation packet processing where deterministic latency and testability are critical.

Availability

71V3557S75PFG8 is available at Aetrix Electronics and suitable for high-speed networking equipment, telecom infrastructure, industrial PLCs, and real-time embedded controllers requiring stable component supply, long-term lifecycle support, and guaranteed industrial temperature operation.

Supply support for 71V3557S75PFG8 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 for communications and computing markets.

The IDT71V3557 family was designed specifically for zero-turnaround memory subsystems in packet-switched networks, where eliminating bus idle time between read/write operations directly improves system throughput and reduces controller complexity.

FAQ

What is the maximum clock frequency supported by the 71V3557S75PFG8?

The 71V3557S75PFG8 supports a maximum clock frequency of 100 MHz, corresponding to a 10 ns clock period. This is validated across the full industrial temperature range (–40°C to +85°C) and ensures reliable 7.5 ns clock-to-data access time under specified VDD/VDDQ conditions. The 71V3557S75PFG8 achieves this performance using IDT's high-speed CMOS process and flow-through output architecture.

Does the 71V3557S75PFG8 support both linear and interleaved burst sequences?

Yes, the 71V3557S75PFG8 supports both linear and interleaved burst orders via the LBO (Linear/Interleaved Burst Order) pin. When LBO = LOW, the burst sequence follows linear order (0,1,2,3); when LBO = HIGH, it follows interleaved order (0,2,1,3). The LBO pin is static and must remain stable during burst operation - changing it mid-burst may cause undefined address sequencing in the 71V3557S75PFG8.

How does the ZBT™ feature eliminate bus turnaround dead cycles in the 71V3557S75PFG8?

The ZBT™ (Zero Bus Turnaround) feature in the 71V3557S75PFG8 removes dead cycles by allowing immediate transition between read and write operations without bus idle time. This is achieved through separate R/W control and flow-through outputs - the device accepts a new address/control word on the same clock edge that delivers the previous read result, enabling back-to-back accesses. No external turnaround logic is needed in the 71V3557S75PFG8.

Can the 71V3557S75PFG8 be used in systems requiring IEEE 1149.1 boundary-scan testing?

Yes, the 71V3557S75PFG8 includes an optional IEEE 1149.1-compliant JTAG boundary-scan interface with TMS, TDI, TCK, TDO, and optional TRST pins. All JTAG signals have internal pull-ups, simplifying PCB routing. The 71V3557S75PFG8 supports standard boundary-scan instructions including SAMPLE/PRELOAD, EXTEST, and BYPASS - verified in the official IDT documentation for this part number.

What is the function of the ZZ (Sleep Mode) pin on the 71V3557S75PFG8?

The ZZ pin on the 71V3557S75PFG8 is a synchronous active-high input that gates the internal clock and places the device into low-power sleep mode. In this state, dynamic power drops significantly while data retention is guaranteed across the full industrial temperature range. The 71V3557S75PFG8 resumes normal operation synchronously upon ZZ returning LOW, with no reset or initialization sequence required.