Renesas 71V3557S80PFG8

Overview

71V3557S80PFG8 from Integrated Device Technology is a 128K × 36-bit (4.5 Mbit), 3.3V synchronous ZBT™ SRAM with flow-through outputs, 100 MHz clock speed, and zero bus turnaround architecture. It supports interleaved/linear 4-word burst reads/writes, individual byte write control (BW1–BW4), and JTAG boundary scan (IEEE 1149.1). Used in high-speed packet buffering and cache coherency logic in telecom switching fabric.

For engineers reviewing the 71V3557S80PFG8 datasheet, 71V3557S80PFG8 pinout, 71V3557S80PFG8 application, or 71V3557S80PFG8 equivalent, key selection criteria include ZBT™ timing compliance, TQFP-100 package compatibility, 3.3V I/O and core supply tolerance, burst counter behavior under ADV/LD control, and sleep mode (ZZ) power-down capability.

Technical Context

The 71V3557S80PFG8 implements a synchronous dual-register architecture: address/control inputs are latched on the rising CLK edge when CEN is low and chip enables (CE1, CE2, CE2) are asserted; data input is registered, while output is flow-through (no output register). Burst sequencing is controlled by LBO and advanced via ADV/LD high transitions.

Its ZBT™ operation eliminates dead cycles between read/write transitions by allowing immediate bus direction reversal - enabled by internal synchronization of OE and absence of output register delay. Sleep mode (ZZ high) gates CLK internally while guaranteeing data retention, and JTAG test access uses TMS/TDI/TCK/TDO/TRST pins per IEEE 1149.1.

Key Specifications

Pinout & Package

71V3557S80PFG8 is packaged in a JEDEC-standard 100-pin thin quad flatpack (TQFP), 14 mm × 20 mm body, 0.5 mm pitch. Pin 1 marked by dot; top-side marking includes "71V3557S80PFG8" and date code.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1355BV18-100BZI and AS7C33128PFSIG, the 71V3557S80PFG8 uniquely delivers ZBT™-enabled bus efficiency, integrated 4-word burst counter, and JTAG testability in a TQFP-100 package - making it optimal for telecom and industrial systems demanding deterministic latency and production test coverage.

Availability

71V3557S80PFG8 is available at Aetrix Electronics and suitable for packet buffering, cache coherency, baseband processing, and industrial motion control applications requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for 71V3557S80PFG8 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 71V3557S80PFG8 belongs to IDT's ZBT™ SRAM product line, designed specifically for high-speed networking and real-time embedded systems where deterministic latency, bus efficiency, and robust testability are mandatory.

FAQ

What is the maximum clock frequency supported by the 71V3557S80PFG8?

The 71V3557S80PFG8 supports a maximum clock frequency of 100 MHz, corresponding to a 7.5 ns clock-to-data access time. This specification is guaranteed across the full industrial temperature range (–40°C to +85°C) and 3.3 V ±5% supply conditions. The 71V3557S80PFG8 achieves this performance using IDT's high-speed CMOS process and flow-through output architecture, eliminating output register delay.

How does the ZBT™ feature of the 71V3557S80PFG8 eliminate dead cycles?

The ZBT™ (Zero Bus Turnaround) feature of the 71V3557S80PFG8 eliminates dead cycles by enabling immediate reversal of bus direction between read and write operations without requiring wait states. This is achieved through synchronous control of R/W and OE, combined with flow-through outputs and internally synchronized output enable - allowing the 71V3557S80PFG8 to drive valid data or accept new write data on consecutive clock edges.

What is the function of the ADV/LD pin on the 71V3557S80PFG8?

The ADV/LD pin on the 71V3557S80PFG8 serves a dual role: when sampled low at the rising CLK edge, it loads a new external address into the address register; when sampled high, it advances the internal burst counter to generate the next sequential or interleaved address. This pin is central to the 71V3557S80PFG8's burst operation and must be driven synchronously with CLK and chip enables.

Does the 71V3557S80PFG8 support JTAG boundary scan, and which pins are used?

Yes, the 71V3557S80PFG8 supports IEEE 1149.1-compliant JTAG boundary scan. The required pins are TMS (Test Mode Select), TDI (Test Data Input), TCK (Test Clock), TDO (Test Data Output), and optional TRST (JTAG Reset). These signals are dedicated and mapped to specific pins in the TQFP-100 package - confirmed in the official IDT datasheet DSC-5282/09.

Can the 71V3557S80PFG8 operate in low-power mode, and how is it activated?

Yes, the 71V3557S80PFG8 supports low-power sleep mode activated by driving the ZZ pin high. When ZZ is asserted, the internal clock is gated and dynamic power consumption is minimized while memory contents are retained. This mode is synchronous and requires ZZ to be sampled high at the rising edge of CLK, with data retention guaranteed across the full industrial temperature range.