The XC3S1000-5FG320C is a high-performance, cost-optimized field-programmable gate array (FPGA) from AMD Xilinx’s Spartan-3 family. Designed for high-volume, cost-sensitive applications, this device delivers 1,000,000 system gates, flexible I/O capabilities, and industry-leading programmability — all in a compact 320-ball Fine-Pitch BGA (FBGA) package. Whether you are designing embedded systems, digital signal processing pipelines, or communications hardware, the XC3S1000-5FG320C offers the logic density and speed performance engineers demand.

For a broad selection of compatible solutions, visit Xilinx FPGA.

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What Is the XC3S1000-5FG320C?

The XC3S1000-5FG320C belongs to the Spartan-3 generation of Xilinx FPGAs — a family specifically engineered to lower the cost per logic cell while maintaining robust performance. The “5” in the part number designates the speed grade, with -5 being the fastest available grade in this family, making this device ideal for timing-critical designs. The “FG320” denotes the 320-ball Fine-Pitch BGA package, and the trailing “C” indicates the commercial temperature range (0°C to +85°C).

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XC3S1000-5FG320C Key Specifications

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XC3S1000-5FG320C Functional Overview

Logic Architecture

The XC3S1000-5FG320C is built around Xilinx’s Configurable Logic Block (CLB) architecture. Each CLB contains four slices, and each slice includes two 4-input Look-Up Tables (LUTs), two storage elements (flip-flops or latches), and dedicated carry logic. This gives designers enormous flexibility in implementing combinational and sequential logic across 17,280 total logic cells.

The device provides 120 Kb of distributed RAM (implemented within the LUTs) and 432 Kb of dedicated Block RAM organized as 18 Kb blocks. This combination makes the XC3S1000-5FG320C well-suited for buffering, FIFO design, and on-chip storage.

Digital Clock Management (DCM)

Four on-chip Digital Clock Managers (DCMs) provide powerful clock manipulation features, including:

• Clock frequency synthesis and multiplication
• Phase shifting and deskewing
• Clock mirroring and division
• Duty cycle correction

These DCMs eliminate the need for external clock conditioning circuitry, simplifying PCB design and reducing system cost.

Dedicated Multipliers

With 24 dedicated 18×18-bit hardware multipliers, the XC3S1000-5FG320C accelerates DSP and arithmetic-intensive operations. These multipliers can be cascaded or used in parallel to build multiply-accumulate (MAC) structures for signal processing, motor control, and image processing pipelines.

I/O Architecture and Standards

The XC3S1000-5FG320C supports a wide range of single-ended and differential I/O standards, providing maximum flexibility for interfacing with external devices.

Each I/O bank can be independently powered, allowing mixed-voltage designs on a single device.

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Package Information: FG320 Fine-Pitch BGA

The XC3S1000-5FG320C is housed in a 320-ball Fine-Pitch BGA (FBGA) package with a 1.00 mm ball pitch and a 19mm × 19mm body size. This compact, surface-mount package is appropriate for space-constrained PCB designs and supports automated reflow soldering processes.

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Speed Grade -5: What It Means for Your Design

The -5 speed grade is the fastest available for the Spartan-3 1000K family. A higher speed grade (lower absolute number for Xilinx) translates to tighter timing parameters, including:

• Faster combinatorial logic propagation delays through LUTs and interconnects
• Higher maximum clock frequencies for synchronous designs
• Shorter setup and hold times, enabling operation with faster external interfaces
• Better performance margins in tight timing closure scenarios

Designers targeting demanding clock frequencies — for example, processors, high-speed serial bridges, or memory controllers — should prioritize the -5 grade over the slower -4 variant.

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XC3S1000-5FG320C Electrical Characteristics

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Supported Design Tools and Programming

Xilinx ISE Design Suite

The XC3S1000-5FG320C is fully supported by the Xilinx ISE Design Suite, particularly ISE 14.7 — the last version with Spartan-3 family support. ISE provides:

• HDL synthesis (VHDL and Verilog)
• Place-and-route tools optimized for Spartan-3 architecture
• Timing analysis and constraint management (UCF files)
• FPGA Editor for manual placement review
• iMPACT programming tool for JTAG and configuration

Configuration Modes

The device retains its configuration in an external non-volatile memory (PROM) since Spartan-3 devices are SRAM-based and require reconfiguration on every power-up.

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Typical Applications for the XC3S1000-5FG320C

The XC3S1000-5FG320C is a versatile device suited for a broad range of embedded and signal processing applications.

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XC3S1000-5FG320C vs. Other Spartan-3 Variants

The table below compares the XC3S1000 to neighboring devices in the Spartan-3 family to help designers select the right density.

The XC3S1000 occupies the mid-range of the Spartan-3 family — offering significantly more logic density than the XC3S400 while remaining more cost-effective than the XC3S1500 and above.

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Ordering Information

Note: For industrial temperature range requirements (-40°C to +100°C), consider the XC3S1000-5FG320I variant.

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Frequently Asked Questions (FAQ)

What does the “-5” speed grade mean on the XC3S1000-5FG320C?

The “-5” denotes Xilinx’s fastest speed grade for the Spartan-3 1000K device. It provides the lowest propagation delays and supports the highest clock frequencies within this device variant.

Is the XC3S1000-5FG320C RoHS compliant?

Yes, the XC3S1000-5FG320C is RoHS compliant and uses lead-free solder ball material in the FBGA package.

What software is used to program the XC3S1000-5FG320C?

Xilinx ISE Design Suite (version 14.7 recommended) is the primary design tool. Configuration is performed using the iMPACT programmer via JTAG, or via a Xilinx Platform Flash PROM for standalone operation.

Can I replace the XC3S1000-5FG320C with a newer Xilinx FPGA?

For new designs, AMD Xilinx recommends migrating to the Artix-7 family (e.g., XC7A35T or XC7A50T), which offers lower power, higher performance, and modern tool support through Vivado Design Suite. The Spartan-3 family remains fully supported for existing production designs.

What is the difference between XC3S1000-5FG320C and XC3S1000-5FG320I?

The only difference is the operating temperature range. The “C” suffix designates the commercial grade (0°C to +85°C), while the “I” suffix designates the industrial grade (-40°C to +100°C).

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Summary

The XC3S1000-5FG320C is a proven, cost-effective FPGA that delivers 1 million system gates, 17,280 logic cells, 432 Kb of block RAM, 24 dedicated hardware multipliers, and four digital clock managers — all housed in a compact 320-ball Fine-Pitch BGA package. Its -5 speed grade ensures maximum timing performance, making it a reliable choice for embedded processing, DSP, communications, and industrial control applications. Backed by Xilinx ISE tooling and broad I/O standard support, this device continues to be a trusted component in both legacy and new designs across a wide range of industries.