The XC4085XLA-O9BG352I is a high-performance, high-capacity Field Programmable Gate Array (FPGA) from the Xilinx XC4000XLA family. Designed for industrial-grade applications, this device delivers 85,000 equivalent logic gates, a 352-pin BGA package, and a 3.3V operating voltage — making it a trusted choice for engineers working in aerospace, defense, communications, and embedded control systems.

If you are sourcing a Xilinx FPGA for a legacy system, new design, or board-level replacement, the XC4085XLA-O9BG352I offers the architectural depth and I/O density required for demanding, real-world projects.

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What Is the XC4085XLA-O9BG352I?

The XC4085XLA-O9BG352I belongs to Xilinx’s XC4000XLA series — a mature and well-documented FPGA family built on 0.35µm CMOS technology. The device is configured via SRAM-based programming cells, allowing unlimited reprogrammability. It combines configurable logic blocks (CLBs), hierarchical routing, and programmable I/O blocks (IOBs) into a flexible, scalable architecture suited for complex digital designs.

Originally manufactured by Xilinx (now AMD), this part is currently distributed by Rochester Electronics LLC as an authorized lifecycle extension source.

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Key Features of the XC4085XLA-O9BG352I FPGA

• 85,000 equivalent logic gates for high-density design implementation
• 7,448 logic cells organized in Configurable Logic Blocks (CLBs)
• 352-pin Ball Grid Array (BGA) package for compact, high-density PCB mounting
• 3.3V core supply voltage aligned with standard digital logic systems
• 227 MHz maximum operating frequency for high-speed applications
• 0.35µm CMOS process technology ensuring low power and proven reliability
• SRAM-based configuration — unlimited reprogramming capability
• Industrial temperature grade (I) for operation in harsh environments
• XC4000XLA family architecture with abundant routing resources and versatile CLB structure

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XC4085XLA-O9BG352I Technical Specifications

General Specifications

Logic & Capacity

Performance

Package & Physical

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XC4085XLA-O9BG352I Part Number Decoder

Understanding the part number helps engineers verify they are ordering the correct variant for their application.

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XC4000XLA Architecture Overview

H3: Configurable Logic Blocks (CLBs)

The XC4085XLA-O9BG352I is built around a regular array of CLBs. Each CLB contains two 4-input lookup tables (LUTs), carry logic, and multiple flip-flops. This architecture enables efficient implementation of both combinational and sequential logic functions. The CLBs can also be used as distributed RAM, adding flexibility for data buffering and state storage without external memory.

H3: Programmable Routing Resources

Xilinx’s hierarchical routing architecture in the XC4000XLA family provides three levels of routing: local CLB-to-CLB connections, long lines spanning the full width or height of the device, and global clock distribution networks. This routing hierarchy ensures that timing closure is achievable even for complex, high-fanout designs.

H3: Programmable Input/Output Blocks (IOBs)

Each pin of the XC4085XLA-O9BG352I connects to a fully programmable IOB. Each IOB supports input, output, and bidirectional configurations. Features include programmable slew rate control, output drive strength selection, and optional input/output registers. The 352-pin BGA package provides a substantial number of user I/Os for interfacing with memory, buses, sensors, and communication peripherals.

H3: Clock Distribution & DLL Support

The XC4000XLA family incorporates Delay-Locked Loops (DLLs) for clock skew reduction and phase alignment. This is critical for high-speed, synchronous designs operating near the 227 MHz maximum frequency of the XC4085XLA-O9BG352I. Global clock lines ensure uniform clock distribution across all CLBs and IOBs.

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Configuration Methods

The XC4085XLA-O9BG352I supports multiple configuration modes, enabling flexible system integration:

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Typical Applications

The XC4085XLA-O9BG352I is well-suited for a wide range of demanding applications that require reconfigurable logic, high I/O counts, and industrial-grade reliability.

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Why Choose the XC4085XLA-O9BG352I for Industrial Designs?

Proven & Mature Architecture

The XC4000XLA family has been deployed in mission-critical systems for over two decades. Its architecture is thoroughly documented, and a broad base of legacy designs rely on it. For engineers maintaining or replicating existing equipment, the XC4085XLA-O9BG352I provides a directly compatible drop-in solution.

Industrial Temperature Compliance

The “-I” suffix designates industrial temperature grade operation from –40°C to +100°C junction temperature. This makes the part suitable for outdoor enclosures, harsh factory floors, automotive support electronics, and military-adjacent applications where consumer-grade components would fail.

Unlimited Reprogrammability

Because the XC4085XLA-O9BG352I uses SRAM-based configuration cells, the device can be reconfigured in-system as many times as needed. This is a major advantage during development, field upgrades, and adaptive system design where hardware functionality may need to evolve over time.

High Logic Density in a Compact BGA Package

The 352-pin BGA package packs 85,000 equivalent gates into a compact footprint, freeing up board space while maintaining a high user I/O count. This is especially valuable in space-constrained PCB designs typical of embedded and avionics equipment.

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XC4085XLA-O9BG352I vs. Related Variants

Engineers often compare the XC4085XLA-O9BG352I with other variants in the same product family. The table below highlights the key differences to support part selection.

Note: The “I” suffix = Industrial temperature range (–40°C to +100°C). The “C” suffix = Commercial temperature range (0°C to +85°C). The “-09” speed grade offers a propagation delay of 9 ns; lower numbers (e.g., “-07”) indicate faster devices.

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Design Tools & Software Support

The XC4085XLA-O9BG352I is supported by Xilinx legacy design tools. While modern Xilinx devices use the Vivado Design Suite, the XC4000XLA family was originally developed with:

• Xilinx ISE Design Suite — Synthesis, implementation, place & route, bitstream generation
• Foundation Series — Earlier generation Xilinx design environment
• XST (Xilinx Synthesis Technology) — HDL synthesis engine
• ModelSim / Synopsys VCS — Third-party simulation support
• JTAG programming tools — iMPACT and third-party JTAG programmers

Engineers migrating legacy XC4000XLA designs to newer devices may use the ISE to Vivado migration path as a starting point for porting to Spartan-6 or Artix-7 class FPGAs.

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Ordering Information

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Frequently Asked Questions (FAQ)

Q: Is the XC4085XLA-O9BG352I still in production?
A: No. This part is classified as obsolete by Xilinx (AMD). However, it remains available through authorized lifecycle distributors such as Rochester Electronics, which maintains certified stock of legacy components.

Q: What is the difference between XC4085XLA-O9BG352I and XC4085XLA-09BG352I?
A: These are the same part. The “O9” and “09” designations both refer to the speed grade; the variant with “O” (letter O) is simply an alternate formatting of the numeric “0” (zero). Always confirm with your distributor.

Q: Can I replace the XC4085XLA-O9BG352I with a newer Xilinx FPGA?
A: Functional migration is possible using modern Xilinx FPGAs such as the Spartan-6 or Artix-7 series, but it requires RTL porting and layout changes due to different package footprints and toolchain requirements. The XC4085XLA-O9BG352I is the recommended choice for direct, pin-compatible board replacement.

Q: What configuration voltage does the XC4085XLA-O9BG352I require?
A: The device operates at 3.3V. Configuration pins and I/O voltage levels are also 3.3V compatible. Refer to the Xilinx XC4000XLA datasheet for detailed electrical specifications.

Q: Is the XC4085XLA-O9BG352I suitable for military or aerospace applications?
A: The industrial-grade (“I”) version covers –40°C to +100°C, making it appropriate for many military-adjacent and aerospace support applications. For full MIL-SPEC certification, confirm with your supplier regarding lot traceability and screening.

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Summary

The XC4085XLA-O9BG352I is a proven, high-density FPGA from the Xilinx XC4000XLA family. With 85,000 equivalent gates, 7,448 logic cells, a 352-pin BGA package, 3.3V operation, and an industrial temperature rating, it remains a critical component for legacy system maintenance, defense electronics, and industrial control applications. Its SRAM-based architecture supports unlimited reconfigurability, and its mature ecosystem of design tools ensures continued engineering support.

Whether you are replacing a failed component on an existing board or designing a new system around a proven FPGA architecture, the XC4085XLA-O9BG352I delivers the logic density, I/O flexibility, and operating reliability your design demands.