The XC4085XLA-08BG432C is a high-performance, high-capacity Field Programmable Gate Array (FPGA) from Xilinx’s XC4000XLA family, distributed by Rochester Electronics. Featuring 85,000 system gates, 7,448 logic cells, and housed in a 432-pin BGA package, this device is engineered for complex digital logic designs that demand speed, flexibility, and proven reliability. Whether you are maintaining legacy industrial systems or sourcing components for mission-critical applications, the XC4085XLA-08BG432C delivers the performance and density required.

For engineers designing or procuring Xilinx FPGA solutions, this part offers a mature, well-documented architecture backed by extensive field deployment history.

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XC4085XLA-08BG432C Key Specifications at a Glance

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What Is the XC4085XLA-08BG432C? An Overview of the XC4000XLA FPGA Family

The XC4085XLA-08BG432C belongs to Xilinx’s XC4000XLA/XV Field Programmable Gate Array series — one of the most widely adopted FPGA families in the history of digital design. Built on a refined 0.35 µm CMOS process, the XC4000XLA devices offer lower power consumption and enhanced routing efficiency compared to earlier XC4000XL variants, while maintaining full architectural and package compatibility.

The “-08” speed grade designation indicates the device’s timing performance tier within the XLA lineup, while “BG432C” identifies the 432-pin Ball Grid Array commercial-grade package. This combination makes the XC4085XLA-08BG432C a high-density option for designs requiring maximum I/O in a compact BGA footprint.

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XC4085XLA-08BG432C Detailed Technical Specifications

Logic Architecture and Gate Density

The XC4085XLA-08BG432C provides approximately 85,000 equivalent system gates implemented through 7,448 logic cells organized into 3,136 Configurable Logic Blocks (CLBs). Each CLB contains two independent 4-input look-up tables (LUTs) capable of implementing any logic function, plus integrated flip-flops for sequential logic.

Speed and Timing Performance

Package and Pin Information

Power and Electrical Characteristics

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XC4085XLA-08BG432C CLB Architecture Deep Dive

How the Configurable Logic Block (CLB) Works

The Configurable Logic Block is the fundamental building unit of the XC4000XLA series. Each CLB in the XC4085XLA-08BG432C contains:

• Two independent function generators (F and G), each a 4-input LUT capable of realizing any Boolean function of up to 4 variables.
• A third function (H) that can combine outputs of F and G with an additional input.
• Two edge-triggered D flip-flops for sequential logic with synchronous and asynchronous set/reset controls.
• Internal multiplexers for flexible routing of signals between function generators and storage elements.

This architecture enables efficient implementation of arithmetic logic, memory structures (distributed RAM), shift registers, and complex combinatorial functions within a single CLB.

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Clock and Timing Resources

The XC4085XLA-08BG432C features eight global low-skew clock networks that distribute clock signals across the entire device with minimal skew. These dedicated clock resources ensure reliable timing closure in high-speed, multi-clock designs and are essential for meeting setup and hold time requirements across all 3,136 CLBs.

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I/O Standards and Signal Integrity

Supported I/O Standards

The XC4085XLA-08BG432C supports multiple I/O standards, making it ideal for interfacing with both legacy 5V TTL logic systems and modern 3.3V LVTTL components. Programmable slew rate control and drive strength options allow engineers to optimize signal integrity and minimize EMI for specific board designs.

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Configuration Modes for XC4085XLA-08BG432C

The XC4085XLA-08BG432C supports several industry-standard configuration modes, providing flexibility in system design:

JTAG Boundary Scan

The device is fully compliant with IEEE 1149.1 JTAG boundary scan, enabling in-system testing, board-level diagnostics, and fault isolation without physical probing. Readback capability allows verification of internal configuration and logic states during development.

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XC4085XLA-08BG432C Part Number Decoder

Understanding the part number helps confirm you are ordering the exact device needed for your application:

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Typical Applications for the XC4085XLA-08BG432C

The XC4085XLA-08BG432C has been widely deployed across a broad range of industries due to its logic density, I/O flexibility, and proven reliability:

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XC4085XLA-08BG432C vs. Other XC4085XLA Speed Grades

Engineers evaluating the XC4085XLA-08BG432C often compare it against other speed grades within the same XC4085XLA family. The table below summarizes the key differences:

The -08 speed grade strikes a balance between performance and availability, making it a popular choice for designs that require solid performance without mandating the tightest (and often scarcer) -07 parts.

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Ordering Information and Availability

The XC4085XLA-08BG432C is distributed by Rochester Electronics, a licensed manufacturer authorized to produce and supply end-of-life and legacy Xilinx components. Rochester Electronics ensures continued supply chain support for products that are no longer in active production by the original manufacturer.

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Why Choose the XC4085XLA-08BG432C for Your Legacy FPGA Design?

• Proven reliability — The XC4000XLA family has decades of field deployment across industrial, military, and telecom applications.
• High logic density — 85,000 gates and 7,448 logic cells support complex, feature-rich designs.
• Flexible I/O — 432-pin BGA with support for 5V TTL, 3.3V LVTTL, and PCI I/O standards.
• Programmable clocking — Eight global low-skew clock networks for reliable timing in multi-clock designs.
• Multiple configuration modes — JTAG, serial, and parallel configuration options for maximum design flexibility.
• Authorized supply — Available through Rochester Electronics, ensuring authentic, quality-controlled components.

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Frequently Asked Questions (FAQ)

Q: What is the core supply voltage for the XC4085XLA-08BG432C? A: The device operates on a 3.3V core supply voltage.

Q: Is the XC4085XLA-08BG432C RoHS compliant? A: No. As a legacy component, this device is not RoHS compliant. Designers in regions or industries requiring RoHS compliance should verify regulatory requirements before use.

Q: What software tools are compatible with the XC4085XLA-08BG432C? A: The XC4000XLA family is supported by Xilinx ISE Design Suite (Foundation Series). Note that this family is not supported in Vivado, which targets newer Xilinx device families.

Q: Can the XC4085XLA-08BG432C be used in new designs? A: While the device is technically capable, Xilinx classifies the XC4000XLA family as not recommended for new designs (NRND). It is primarily sourced for legacy system maintenance, repair, and obsolescence management.

Q: What is the difference between the -08 and -09 speed grade? A: The -08 speed grade is faster than the -09. Lower speed grade numbers indicate higher performance (shorter propagation delays and higher maximum operating frequencies).