Renesas 71V3556SA133BQGI8

Overview

71V3556SA133BQGI8 from IDT (now Renesas) is a 3.3V, 128K × 36-bit synchronous ZBT™ SRAM with zero bus turnaround, 133 MHz operation (7.5 ns clock-to-data), pipelined outputs, and JTAG boundary scan support. It features 4-word burst (linear/interleaved), individual byte write control (BW1–BW4), and operates across –40°C to +85°C for industrial embedded memory subsystems.

For engineers reviewing the 71V3556SA133BQGI8 datasheet, 71V3556SA133BQGI8 pinout, 71V3556SA133BQGI8 application, or 71V3556SA133BQGI8 equivalent, key selection criteria include ZBT™ bus efficiency, 100-pin TQFP packaging, synchronous R/W control with ADV/LD address management, and JTAG-compliant testability in high-speed cache or buffer designs.

Technical Context

The 71V3556SA133BQGI8 implements a fully synchronous, rising-edge-triggered architecture with registered address, data, and control inputs. Its ZBT™ feature eliminates dead cycles between read/write transitions by decoupling bus direction control from OE-output enable is asynchronous but internally synchronized via clocked output registers.

It integrates a 4-word burst counter controlled by ADV/LD and LBO, supports depth expansion via three chip enables (CE1, CE2, CE2), and includes optional IEEE 1149.1 JTAG boundary scan (TMS/TDI/TCK/TDO/TRST) for system-level testability-all within a single 3.3V core/I/O supply domain.

Key Specifications

Pinout & Package

Packaged in a JEDEC-standard 100-pin plastic thin quad flatpack (TQFP), 14 mm × 20 mm body, lead pitch 0.5 mm. Pin 64 supports ZZ (sleep mode) on latest die revision; pins 14/16/66 tolerate VIH-level input without direct VDD connection.

Key Features

Applications

Equivalent & Alternatives

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

Compared with 71V3556SA133BQGI8, the 166 MHz variant offers higher throughput headroom while the non-JTAG 'S' version reduces pin count overhead and test infrastructure requirements-both retain full ZBT™ functionality and industrial temperature support.

Availability

71V3556SA133BQGI8 is available at Aetrix Electronics and suitable for high-speed network buffers, industrial PLC caches, avionics sensor fusion, and medical imaging frame stores requiring stable component supply and long-term industrial lifecycle support.

Supply support for 71V3556SA133BQGI8 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

IDT (Integrated Device Technology), now part of Renesas Electronics, is a semiconductor company specializing in high-performance timing, memory interface, and RF solutions for communications and industrial markets.

The 71V3556SA series belongs to IDT's ZBT™ SRAM product line, engineered specifically for zero-latency, high-bandwidth memory subsystems in networking, aerospace, and real-time control applications.

FAQ

What does the 'SA' suffix indicate in 71V3556SA133BQGI8?

The 'SA' suffix denotes inclusion of IEEE 1149.1 JTAG boundary scan functionality-confirmed by presence of TMS, TDI, TCK, TDO, and optional TRST pins in the 100-pin TQFP package. This distinguishes it from the base 'S' version (e.g., 71V3556S133BQGI8), which leaves those pins as no-connect. The 71V3556SA133BQGI8 uses the same core ZBT™ SRAM architecture but adds testability for complex system integration.

How does the ZBTTM feature eliminate dead cycles in 71V3556SA133BQGI8?

The ZBTTM feature in 71V3556SA133BQGI8 removes bus turnaround latency by decoupling read/write direction control from output enable (OE). Unlike conventional SRAMs requiring OE deassertion before bus reversal, the 71V3556SA133BQGI8 uses internally synchronized output registers that allow immediate transition between read and write cycles-no idle clocks are inserted, enabling continuous data flow at full clock rate.

What is the function of the ADV/LD pin in 71V3556SA133BQGI8?

The ADV/LD pin in 71V3556SA133BQGI8 serves dual roles: when sampled low at the rising clock edge, it loads a new external address into the internal register; when sampled high, it advances the internal 4-word burst counter. This eliminates separate address strobes during burst sequences-reducing control logic complexity and improving timing predictability in pipelined systems using the 71V3556SA133BQGI8.

Can 71V3556SA133BQGI8 operate with only one chip enable asserted?

No-71V3556SA133BQGI8 requires simultaneous assertion of CE1 = LOW, CE2 = LOW, and CE2 = HIGH to select the device. If any one of these three chip enables is inactive (CE1 or CE2 high, or CE2 low), the device enters deselect mode-even if ADV/LD is low. Deselect completes in two clock cycles, after which the data bus goes high-impedance. This triple-enable scheme prevents partial activation and ensures robust depth expansion control in multi-SRAM configurations.

What burst modes does 71V3556SA133BQGI8 support and how are they selected?

The 71V3556SA133BQGI8 supports both linear and interleaved 4-word burst sequences, selected by the static LBO (Linear Burst Order) pin: LBO = LOW configures linear order (A0, A0+1, A0+2, A0+3), while LBO = HIGH selects interleaved order (A0, A0+2, A0+1, A0+3). The burst counter advances on each rising CLK edge when ADV/LD is high, and wraps automatically after the fourth word-enabling efficient sequential access without repeated address setup in the 71V3556SA133BQGI8.