Renesas 71V3556SA166BG8

Overview

71V3556SA166BG8 from Renesas is a 3.3V synchronous ZBT SRAM with 128K × 36-bit organization (4.5 Mbit), 166 MHz operation, 3.5 ns clock-to-data access, zero bus turnaround architecture, and pipelined outputs. It supports interleaved/linear 4-word burst reads/writes, individual byte write control (BW1–BW4), and JTAG boundary scan (IEEE 1149.1) in BGA packaging - used in high-speed networking packet buffers and telecom line-card memory subsystems.

For engineers reviewing the 71V3556SA166BG8 datasheet, 71V3556SA166BG8 pinout, 71V3556SA166BG8 application, or 71V3556SA166BG8 equivalent, key selection criteria include ZBT timing compliance, 3.3V I/O compatibility, industrial temperature support (–40°C to +85°C), burst counter behavior under ADV/LD control, and BGA-119 package mechanical constraints for PCB layout and thermal management.

Technical Context

The 71V3556SA166BG8 implements a fully synchronous, positive-edge-triggered pipeline: address/control registers sample on CLK rising edge with CEN low, and data transfers occur two cycles later. Its ZBT architecture eliminates dead cycles between read/write transitions by decoupling bus direction control from OE and using internal synchronization of output enable.

It integrates a programmable burst counter (LBO-selectable linear/interleaved), three chip enables (CE1, CE2 active-low; CE2 active-high) for depth expansion, and optional IEEE 1149.1 JTAG test interface with TMS/TDI/TCK/TDO/TRST pins - all implemented in a high-performance CMOS process with separate VDD (core) and VDDQ (I/O) supplies.

Key Specifications

Pinout & Package

71V3556SA166BG8 is packaged in a 119-ball fine-pitch BGA (BG119) per JEDEC MO-207AB, with 1.0 mm ball pitch, 14 mm × 14 mm body size, and exposed thermal pad. Pin functions are defined for the 128K × 36 configuration; unused pins (e.g., NC) are no-connect in this variant.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1370DV18-167BZI and AS7C33128PFSIG, the 71V3556SA166BG8 uniquely delivers zero-bus-turnaround timing with integrated burst control and JTAG testability - making it optimal for high-reliability, high-speed embedded memory subsystems requiring both performance and verifiability.

Availability

71V3556SA166BG8 is available at Aetrix Electronics and suitable for packet buffering, telecom line-card caching, industrial PLC data logging, test equipment pattern storage, and JTAG-enabled system diagnostics requiring stable component supply across extended product lifecycles.

Supply support for 71V3556SA166BG8 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

Renesas Electronics is a global semiconductor leader delivering microcontrollers, analog, power, and memory solutions for automotive, industrial, and infrastructure markets.

The 71V3556SA166BG8 belongs to Renesas' ZBT SRAM product line, engineered specifically for high-speed, low-latency memory subsystems in networking, telecom, and test equipment where deterministic timing and bus efficiency are critical.

FAQ

What is the memory organization and total capacity of the 71V3556SA166BG8?

The 71V3556SA166BG8 is organized as 128K × 36 bits, delivering a total capacity of 4,718,592 bits (4.5 Mbit). This configuration supports a 36-bit data bus without external width expansion, directly interfacing with 36-bit memory controllers in high-speed networking ASICs and FPGAs.

Does the 71V3556SA166BG8 support both linear and interleaved burst modes?

Yes, the 71V3556SA166BG8 supports both linear and interleaved 4-word burst sequences. The LBO (Linear Burst Order) pin selects the mode: pulled low for linear addressing (A0, A0+1, A0+2, A0+3), high for interleaved (A0, A0+2, A0+1, A0+3). This flexibility matches varying memory controller burst protocols.

How does the ZBT™ architecture eliminate dead cycles in the 71V3556SA166BG8?

The 71V3556SA166BG8 achieves zero bus turnaround by internally synchronizing output enable (OE) and decoupling bus direction control from external timing. Reads and writes can be issued back-to-back without waiting for bus release, enabling continuous data flow at 166 MHz with no idle cycles between operations.

What package type and ball count does the 71V3556SA166BG8 use?

The 71V3556SA166BG8 uses a 119-ball fine-pitch BGA (BG119) package per JEDEC MO-207AB, with 1.0 mm ball pitch and 14 mm × 14 mm body size. This package includes dedicated VDD, VDDQ, and VSS balls for low-noise power delivery and thermal management in dense PCB layouts.

Is JTAG boundary scan supported on the 71V3556SA166BG8, and which pins implement it?

Yes, the 71V3556SA166BG8 supports IEEE 1149.1 JTAG boundary scan. Pins TMS, TDI, TCK, TDO, and optional TRST (with internal pull-up) are assigned to the JTAG interface. These signals are functional only in the "SA" version (as indicated by the "SA" suffix in the part number), confirming full testability integration.