Renesas 71V3557S75BGG8

Overview

71V3557S75BGG8 from Integrated Device Technology is a 128K × 36-bit (4.5 Mbit), 3.3V synchronous ZBT™ SRAM with flow-through outputs, 7.5 ns clock-to-data access at 100 MHz, and integrated burst counter supporting linear/interleaved 4-word sequences. It features three chip enables, individual byte write control (BW1–BW4), and optional IEEE 1149.1 JTAG boundary scan - deployed in high-speed packet buffering and network switch data planes.

For engineers reviewing the 71V3557S75BGG8 datasheet, 71V3557S75BGG8 pinout, 71V3557S75BGG8 application, or 71V3557S75BGG8 equivalent, key selection criteria include ZBT™ zero bus turnaround timing, TQFP-100 package compatibility, synchronous burst read/write capability, sleep mode (ZZ) support, and 3.3V core/I/O supply compliance.

Technical Context

The 71V3557S75BGG8 implements a synchronous dual-register architecture: address/control signals are latched on the rising CLK edge when ADV/LD is low and chip enables are asserted, while data input is registered and output is flow-through (no output register). Burst sequencing is controlled by LBO and advanced via ADV/LD high transitions.

It supports full 36-bit word writes or granular byte writes via BW1–BW4, uses CEN to suspend internal clock propagation without affecting output state, and enters low-power sleep mode (ZZ = HIGH) with guaranteed data retention. The device includes asynchronous OE for output tri-state control and optional JTAG test interface with TMS/TDI/TCK/TDO/TRST pins.

Key Specifications

Pinout & Package

71V3557S75BGG8 is packaged in a JEDEC-standard 100-pin thin quad flatpack (TQFP), 14 mm × 20 mm body, with 0.5 mm pitch. Pin 64 supports ZZ (sleep mode) on latest die revisions; pins 83–84 are reserved for future density expansion.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1371BV25-7BBXC and AS7C33128PFSIG, the 71V3557S75BGG8 uniquely delivers ZBT™ timing, integrated burst counter, sleep mode, and JTAG in a 3.3V TQFP-100 package - making it optimal for high-performance, testable, thermally constrained networking hardware.

Availability

71V3557S75BGG8 is available at Aetrix Electronics and suitable for network packet buffering, high-speed switch fabric memory, and telecom line card buffering requiring stable component supply, long-term lifecycle support, and industrial temperature grade assurance.

Supply support for 71V3557S75BGG8 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 71V3557S75BGG8 belongs to IDT's ZBT™ synchronous SRAM product line, engineered specifically for zero-latency, high-bandwidth data buffering in networking, telecommunications, and real-time embedded systems.

FAQ

What is the memory organization and total capacity of the 71V3557S75BGG8?

The 71V3557S75BGG8 is organized as 128K × 36 bits, delivering 4,718,592 bits (4.5 Mbit) of total memory capacity. It also supports a 256K × 18-bit configuration through address remapping, maintaining identical pinout and timing behavior. This dual-configuration flexibility allows system designers to optimize data bus width without changing the 71V3557S75BGG8 footprint or interface logic.

Does the 71V3557S75BGG8 support true zero bus turnaround (ZBT™) operation?

Yes, the 71V3557S75BGG8 implements ZBT™ (Zero Bus Turnaround) architecture, eliminating dead cycles between consecutive read and write operations. This is achieved via separate address/control and data pipelines, allowing immediate initiation of a write cycle after a read (or vice versa) without bus idle time - a key requirement for high-efficiency packet processing in the 71V3557S75BGG8's target applications.

What package type and pin count does the 71V3557S75BGG8 use?

The 71V3557S75BGG8 uses a JEDEC-standard 100-pin thin quad flatpack (TQFP) package, measuring 14 mm × 20 mm with 0.5 mm lead pitch. Pin 64 is designated for ZZ (sleep mode) on latest die revisions, and pins 83–84 are reserved for future higher-density variants. This TQFP-100 package ensures mechanical robustness and thermal performance suitable for industrial and telecom environments where the 71V3557S75BGG8 is commonly deployed.

How does the burst counter function in the 71V3557S75BGG8?

The 71V3557S75BGG8 includes an on-chip synchronous burst counter that generates four sequential addresses from a single loaded address. Burst order (linear or interleaved) is selected by the static LBO pin. ADV/LD = HIGH advances the counter; ADV/LD = LOW loads a new external address. This burst capability reduces address bus activity by 75% during sequential accesses - a critical optimization for bandwidth-constrained systems using the 71V3557S75BGG8.

Is JTAG boundary scan supported on the 71V3557S75BGG8?

Yes, the 71V3557S75BGG8 includes optional IEEE 1149.1-compliant JTAG boundary scan functionality, implemented via dedicated TMS, TDI, TCK, TDO, and TRST pins. TRST is optional and internally pulled up; if unused, it may be left floating. This feature enables structural testing of PCB interconnects and facilitates in-system programming and debug - adding testability value not found in many competing synchronous SRAMs like the 71V3557S75BGG8's alternatives.