The XC4085XLA-O9BG352C is a high-capacity, high-performance Field Programmable Gate Array (FPGA) from Xilinx’s XC4000XLA family, distributed by Rochester Electronics. Featuring 85,000 system gates, 3,136 Configurable Logic Blocks (CLBs), and a 352-pin BGA package, this device is engineered for complex digital logic applications that demand reliable performance and design flexibility. Whether you are maintaining a legacy embedded system or sourcing a hard-to-find industrial component, the XC4085XLA-O9BG352C delivers proven capability in a compact, scalable footprint.

For engineers seeking a broad selection of programmable logic devices, explore the full range of Xilinx FPGA solutions available to match your design requirements.

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What Is the XC4085XLA-O9BG352C?

The XC4085XLA-O9BG352C belongs to the Xilinx XC4000XLA/XV family, a generation of SRAM-based FPGAs built on a refined 0.35 µm CMOS process. The XC4000XLA series was designed to combine architectural versatility, abundant routing resources, and high logic density — making it one of the most widely deployed FPGA families in legacy industrial, communications, and defense applications.

The “O9” speed grade designator indicates a maximum operating frequency of 227 MHz, placing this device in the mid-to-high performance tier of the XC4085XLA lineup. The 352-pin Micro BGA (MBGA) package offers a compact board footprint while delivering up to 274 user I/O pins, making it well-suited for designs where board space is at a premium.

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Key Specifications at a Glance

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Detailed Technical Description

## Logic Architecture and Gate Density

The XC4085XLA-O9BG352C provides approximately 85,000 usable system gates organized across 3,136 Configurable Logic Blocks. Each CLB contains two independent logic function generators capable of implementing any function of up to four variables, along with dedicated flip-flops for sequential logic. This architecture delivers substantial computational density for state machines, data path logic, bus interfaces, and custom digital controllers.

The 7,448-cell structure supports a wide variety of design implementations, from simple glue logic to complex pipelined architectures.

## Speed Grade and Timing Performance

The –09 speed grade corresponds to a maximum system clock frequency of 227 MHz under standard operating conditions. This performance level makes the XC4085XLA-O9BG352C suitable for time-critical applications including high-speed data processing, protocol controllers, and communication interfaces that operate at tens to hundreds of megahertz.

## Clock Distribution and Timing Control

The device features eight global low-skew clock networks that distribute clock signals across the entire die with minimal skew. This resource ensures reliable timing closure in designs with multiple synchronous clock domains, improving overall system reliability and reducing the risk of setup or hold violations.

## I/O Standards and Signal Integrity

The programmable drive strength and slew rate control allow engineers to fine-tune signal integrity for both high-speed and power-sensitive interfaces on the same device, reducing EMI and simplifying board design.

## Configuration and Programming

The XC4085XLA-O9BG352C uses SRAM-based configuration, which means the device must be configured at power-up from an external source. Supported configuration modes include:

• Master Serial Mode – device loads configuration from an external serial PROM (e.g., XC1700D series)
• Slave Serial Mode – configured by an upstream master FPGA in a daisy-chain topology
• Peripheral/Parallel Mode – configured by a microprocessor over a parallel bus
• Boundary Scan (JTAG) – IEEE 1149.1-compliant in-system programming and debug

The SRAM configuration architecture supports unlimited reprogramming cycles, making it ideal for designs that require field updates or iterative development cycles.

## Package Information

The 352-pin BGA package provides a compact, high-density footprint suitable for space-constrained PCB layouts while still exposing the full I/O complement of the XC4085XLA core.

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Applications for the XC4085XLA-O9BG352C

The XC4085XLA-O9BG352C has been deployed across a broad range of industries since its introduction, and remains in active use in legacy systems today:

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Why Choose the XC4085XLA-O9BG352C for Legacy System Support?

### Long-Term Availability Through Rochester Electronics

The XC4085XLA-O9BG352C is distributed by Rochester Electronics, a world-leading authorized source for end-of-life and legacy semiconductors. Rochester works directly with original manufacturers to provide genuine, traceable components for products that are no longer in standard production. This makes them a critical resource for MRO (Maintenance, Repair, and Overhaul) teams, defense contractors, and industrial OEMs that cannot redesign their platforms.

### Proven SRAM FPGA Technology

The XC4000XLA family introduced significant architectural improvements over prior generations, including lower-power segmented routing and improved CLB efficiency. These design choices contributed to the family’s widespread adoption and the reason many systems built on this architecture remain in service decades later.

### Compatibility and Footprint Consistency

The BG352 package is shared across multiple density points in the XC4000XLA family, which means the XC4085XLA-O9BG352C is pin-compatible with lower-density members of the same family. This preserves the option for density migration without requiring a full PCB redesign, provided the application logic fits within the available resources.

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Ordering and Part Number Breakdown

Understanding the part number helps confirm the correct variant for your application:

Note: The variant listed on DigiKey as XC4085XLA-09BGG352C (with double “G”) is the same device. The “G” suffix in the package code is a Xilinx package descriptor variant used on some documentation and distribution channels. Always verify the full part number with your distributor before placing an order.

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Frequently Asked Questions

Q: Is the XC4085XLA-O9BG352C still in production? The part has reached end-of-life (EOL) status with Xilinx. Rochester Electronics and authorized legacy distributors maintain inventory of genuine, tested stock for ongoing service and repair needs.

Q: What configuration PROM is compatible with this FPGA? The XC1700 series EEPROMs (e.g., XC17S40, XC17S100) are commonly used with XC4000XLA devices in master serial configuration mode.

Q: What design tools support the XC4085XLA-O9BG352C? Xilinx ISE Design Suite (Foundation and WebPACK editions) was the primary toolchain for the XC4000XLA family. While newer tools such as Vivado do not target this family, ISE remains available for legacy design support.

Q: What is the commercial temperature range for the “C” suffix? The “C” suffix denotes the commercial temperature grade: 0°C to +85°C ambient operating temperature.

Q: Is there an industrial temperature version available? Yes. The “I” suffix variant (e.g., XC4085XLA-09BG352I) supports an extended industrial temperature range of –40°C to +100°C.

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Summary

The XC4085XLA-O9BG352C is a robust, high-density FPGA from Xilinx’s XC4000XLA family that delivers 85,000 system gates, 3,136 CLBs, and 227 MHz operation in a 352-pin BGA package. Backed by Rochester Electronics’ authorized legacy sourcing, it remains a reliable choice for maintaining and sustaining complex embedded systems across industrial, communications, defense, and automotive sectors.