Renesas 71V65803S150BQI

Overview

71V65803S150BQI from Renesas Electronics is a 3.3V synchronous ZBT™ SRAM with 256K × 36-bit (9,437,184-bit) organization, 150 MHz clock speed (3.8 ns clock-to-data access), zero bus turnaround architecture, and pipelined burst read/write capability. It supports interleaved or linear 4-word bursts and operates across industrial temperature range (–40°C to +85°C), targeting high-bandwidth memory buffering in network switches and telecom line cards.

For engineers reviewing the 71V65803S150BQI datasheet, 71V65803S150BQI pinout, 71V65803S150BQI application, or 71V65803S150BQI equivalent, key selection criteria include ZBT™ timing compliance, TQFP-100 package compatibility, 3.3V I/O and core supply requirements, burst counter control via ADV/LD and LBO, and support for individual byte write (BW1–BW4) in high-speed packet forwarding systems.

Technical Context

The 71V65803S150BQI implements a fully synchronous, pipelined interface with all address/control/data registers triggered on the positive clock edge. Its ZBT™ architecture eliminates dead cycles between consecutive read and write operations by overlapping bus turnaround with data transfer - enabled by internal synchronization of OE and burst counter logic.

It features three chip enables (CE1, CE2, CE2) with mixed polarity for flexible depth expansion, a static LBO input selecting linear/interleaved burst order, and asynchronous ZZ sleep mode for low-power retention. The device uses separate VDD (core) and VDDQ (I/O) supplies, each regulated at 3.3V ±5%, and supports individual byte write masking without external logic.

Key Specifications

Pinout & Package

71V65803S150BQI is packaged in a JEDEC-standard 100-pin plastic thin quad flatpack (TQFP), 14 mm × 20 mm body size, with exposed pad not specified. Pin functions are fully defined for the 256K × 36 configuration per datasheet revision Nov.12.21.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CY7C1362BV33-167AXC and AS7C33128PFSI-15, the 71V65803S150BQI offers unique LBO-selectable burst ordering and Renesas-specific ZBT™ implementation validated in telecom infrastructure - making it optimal for applications requiring configurable burst patterns and long-term supply continuity.

Availability

71V65803S150BQI is available at Aetrix Electronics and suitable for network packet buffering, telecom line card memory, baseband processing cache, and industrial real-time controller memory requiring stable component supply, extended lifecycle support, and industrial temperature qualification.

Supply support for 71V65803S150BQI 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 Corporation is a global semiconductor leader specializing in microcontrollers, analog, power, and memory solutions for automotive, industrial, and communications markets.

The 71V65803S150BQI belongs to Renesas' high-speed ZBT™ SRAM product line, engineered specifically for zero-latency memory interfacing in packet-switched networks and real-time signal processing systems.

FAQ

What is the maximum operating frequency and corresponding access time for the 71V65803S150BQI?

The 71V65803S150BQI is rated for a maximum clock frequency of 150 MHz, with a guaranteed clock-to-data access time (tCD) of 3.8 ns under industrial conditions. This specification assumes proper setup/hold timing compliance for all synchronous inputs relative to the rising CLK edge, and operation within the recommended 3.3V ±5% supply range and –40°C to +85°C ambient temperature.

Does the 71V65803S150BQI support both linear and interleaved burst modes, and how is the selection made?

Yes, the 71V65803S150BQI supports both linear and interleaved 4-word burst sequences. Selection is controlled by the static LBO (Linear Burst Order) pin: LBO = LOW selects linear order (A0, A1, A2, A3), while LBO = HIGH selects interleaved order (A0, A2, A1, A3). The LBO state must be stable before device initialization and cannot be changed dynamically during burst operation.

How does the ZBTTM feature eliminate dead cycles between read and write operations in the 71V65803S150BQI?

The ZBTTM (Zero Bus Turnaround) feature in the 71V65803S150BQI eliminates dead cycles by internally synchronizing the output enable path and using pipelined address/control registers. When transitioning from a read to a write (or vice versa), the device overlaps bus direction control with the next data transfer - allowing immediate initiation of the subsequent cycle without waiting for bus stabilization. This is implemented in hardware and requires no external logic or timing adjustments.

What are the power supply requirements for the 71V65803S150BQI, and are separate core and I/O rails mandatory?

The 71V65803S150BQI requires two independent 3.3V supplies: VDD (core logic, 3.3V ±5%) and VDDQ (I/O buffers, 3.3V ±5%). These rails must be separately decoupled and may be powered from the same regulator only if its ripple and transient response meet both core logic and I/O drive requirements. The datasheet explicitly specifies distinct voltage tolerances and noise sensitivity for each rail, making separate filtering strongly recommended for signal integrity.

Can the 71V65803S150BQI be used in a 512K × 18-bit configuration, and what design changes are needed?

Yes, the 71V65803S150BQI shares the same die and timing as the 512K × 18-bit variant (71V65603S150BQI), differing only in address pin mapping and internal memory array segmentation. To use 512K × 18 mode, connect A18 as the MSB address, reduce address bus width to A0–A18 (19 bits), and route I/O[0:15] and I/OP1–I/OP2 only. The 71V65803S150BQI datasheet confirms functional equivalence and pin compatibility between these configurations in TQFP-100 package.