The XC4085XLA-09BG432C is a high-capacity, high-performance Field-Programmable Gate Array (FPGA) from the Xilinx XC4000XLA family, distributed by Rochester Electronics. Engineered for demanding digital logic applications, this device delivers approximately 85,000 system gates in a compact 432-pin BGA package — making it a trusted choice for engineers working on legacy systems, networking infrastructure, DSP pipelines, and embedded control designs.

If you are sourcing, evaluating, or integrating Xilinx FPGA components into your design, the XC4085XLA-09BG432C represents one of the most capable devices in the XC4000XLA lineup.

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What Is the XC4085XLA-09BG432C?

The XC4085XLA-09BG432C belongs to Xilinx’s XC4000XLA/XV FPGA family — a product line representing over fifteen years of FPGA design refinement. Built on a 0.35 µm CMOS process technology, the XLA series introduced significant improvements in routing efficiency, power reduction, and logic density compared to earlier XC4000XL variants.

This specific part number breaks down as follows:

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XC4085XLA-09BG432C Key Specifications

The table below summarizes the core electrical and physical specifications of this device.

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XC4085XLA-09BG432C Architecture Overview

Configurable Logic Blocks (CLBs)

The fundamental building block of the XC4085XLA-09BG432C is its Configurable Logic Block (CLB). Each CLB contains two independent logic function units capable of processing up to four inputs each (labeled F1–F4 and G1–G4). These function generators can implement any arbitrary four-input Boolean function, providing extreme design flexibility.

Key CLB features include:

• Two independent look-up table (LUT) function generators per CLB
• Integrated flip-flops with set/reset control for sequential logic
• Internal multiplexers for flexible signal routing via H1 and DIN/H2 inputs
• Dedicated carry-chain logic for fast arithmetic operations

Routing and Interconnect Resources

The XC4000XLA family introduced enhanced routing architecture that significantly reduced routing delays compared to earlier XC4000 variants. The XC4085XLA-09BG432C features abundant long-line, double-length, and single-length routing segments, allowing designers to achieve tight timing closure even in complex, high-fanout designs.

Block RAM and Distributed Memory

The device supports both dedicated carry chains and block RAM resources, enabling efficient implementation of:

• Digital filters (FIR, IIR)
• Fast Fourier Transforms (FFTs)
• Custom memory-mapped register files
• High-throughput FIFO structures

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Configuration Modes

The XC4085XLA-09BG432C supports multiple configuration modes to suit different system architectures.

In a typical Master/Slave Serial daisy-chain setup, the XC4085XLA-09BG432C operates as a slave. A master FPGA or microcontroller drives CCLK and feeds configuration data through the DIN pin. The PROGRAM, INIT, and DONE control signals manage the sequencing, allowing multiple devices to be loaded from a single external PROM such as the XC1700D series.

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I/O and Interface Capabilities

Supported I/O Standards

The XC4085XLA-09BG432C’s PCI-compatible I/O makes it directly suitable for integration into PCI bus architectures without additional level-shifting logic.

JTAG Boundary Scan

Full IEEE 1149.1 JTAG boundary scan support enables:

• In-circuit board-level testing and fault isolation
• Internal state verification via readback
• Non-intrusive debugging during system operation
• Unlimited in-system reprogramming

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Typical Applications

The XC4085XLA-09BG432C’s combination of high gate density, fast clock speeds, and flexible I/O makes it appropriate for a wide range of applications.

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XC4085XLA-09BG432C vs. Related Variants

Engineers often evaluate multiple speed grades and package options. The table below compares the BG432C variant against related parts.

The –09 speed grade balances cost and performance for most commercial applications. The –07 variant is selected when maximum clock frequency is the primary constraint.

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Package Information: 432-Pin BGA

The BGA432 (Ball Grid Array, 432 balls) package provides high pin density in a compact footprint, minimizing PCB area while maximizing I/O count. Key package characteristics:

• Package Type: Plastic BGA (PBGA)
• Ball Count: 432
• Mounting Style: Surface Mount Technology (SMT)
• Pitch: Standard BGA pitch for high-density PCB routing

BGA packages require careful PCB design attention, including via-in-pad or dog-bone routing strategies, adequate decoupling capacitor placement adjacent to the device, and thermal management planning for sustained high-frequency operation.

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Design and Development Tools

The XC4085XLA-09BG432C is supported by Xilinx legacy design tools. For new development targeting this family, engineers typically use:

• Xilinx ISE Design Suite – the primary tool for XC4000-era synthesis, place-and-route, and bitstream generation
• VHDL / Verilog HDL – standard hardware description languages for RTL design
• ModelSim / ISim – simulation tools for functional and timing verification
• ChipScope Pro – in-system logic analysis via JTAG

Because the XC4000XLA family predates Vivado, ISE remains the recommended toolchain for this device.

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Ordering and Sourcing Information

The XC4085XLA-09BG432C is currently distributed by Rochester Electronics LLC, a specialist in licensed, last-time-buy, and long-lifecycle semiconductor supply. Rochester is an authorized Xilinx source, which is particularly important for quality assurance when procuring legacy FPGA devices.

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Frequently Asked Questions (FAQ)

Q: Is the XC4085XLA-09BG432C still in production?
The XC4085XLA series is a legacy product. Rochester Electronics maintains authorized stock and continues to support long-lifecycle procurement for maintenance and production continuity programs.

Q: What is the maximum clock frequency of the XC4085XLA-09BG432C?
The –09 speed grade supports a maximum system frequency of approximately 227 MHz, depending on the implemented logic and routing paths.

Q: Can the XC4085XLA-09BG432C be reprogrammed?
Yes. As an SRAM-based FPGA, it supports unlimited reprogramming. Configuration is reloaded from external non-volatile memory each time the device powers up.

Q: What configuration PROM is compatible?
The Xilinx XC1700D series serial PROMs are commonly paired with XC4000XLA devices for master-mode serial configuration.

Q: Does this device support in-system programming?
Yes. Full IEEE 1149.1 JTAG boundary scan allows in-system configuration updates and board-level diagnostics without physical removal of the device.

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Summary

The XC4085XLA-09BG432C is a proven, high-density FPGA delivering approximately 85,000 system gates, 3,136 CLBs, and a 227 MHz operating speed in a 432-pin BGA package at 3.3 V. Its robust feature set — including JTAG boundary scan, multiple configuration modes, PCI-compatible I/O, and dedicated carry-chain arithmetic — makes it a reliable foundation for networking, DSP, embedded control, and industrial applications. Sourced through Rochester Electronics, engineers can procure this device with full authorization and long-lifecycle supply chain confidence.