The XC3S400-5TQG144C is a high-performance, cost-optimized field-programmable gate array (FPGA) from the Xilinx FPGA Spartan-3 family, now under the AMD product portfolio. Designed for high-volume, cost-sensitive applications, this device delivers 400,000 system gates in a compact 144-pin TQFP package — making it an ideal solution for embedded systems, digital signal processing, communications, and consumer electronics.

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What Is the XC3S400-5TQG144C?

The XC3S400-5TQG144C is a member of the Spartan-3 FPGA family from Xilinx (AMD). The “400” in the part number indicates approximately 400,000 system gates, while the “5” speed grade denotes a faster-than-standard speed rating. The TQG144 refers to the 144-pin Thin Quad Flat Package (TQFP), and the “C” suffix indicates the commercial temperature range (0°C to +85°C).

This device is widely used in applications requiring a balance of logic density, I/O flexibility, and price efficiency.

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XC3S400-5TQG144C Key Specifications

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XC3S400-5TQG144C Package & Pinout Overview

### TQFP-144 Package Details

The TQFP-144 is a standard SMT package suitable for automated PCB assembly. Its compact footprint makes it well-suited for space-constrained designs where BGA packages are not practical.

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Spartan-3 Architecture: Inside the XC3S400-5TQG144C

### Configurable Logic Blocks (CLBs)

The XC3S400-5TQG144C contains 1,260 CLBs, each consisting of four slices. Every slice includes two 4-input LUTs (Look-Up Tables), two storage elements (flip-flops or latches), and dedicated carry/arithmetic logic. This gives designers a total of 16,128 flip-flops and substantial combinatorial logic resources.

### Block RAM

The device integrates 18 block RAM tiles, providing 288 Kb of true dual-port synchronous block memory. Each 18-Kb tile can be configured as 16K×1, 8K×2, 4K×4, 2K×9, 1K×18, or 512×36 — offering significant flexibility for FIFOs, data buffers, and lookup tables.

### Dedicated Multiplier Blocks

20 dedicated 18×18-bit multipliers are embedded in the silicon, enabling high-throughput DSP functions such as digital filters, FFT engines, and correlation without consuming CLB resources.

### Digital Clock Managers (DCMs)

The 4 integrated DCMs support clock multiplication, division, phase shifting, and de-skewing — essential for synchronizing clocks across complex multi-domain digital designs.

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I/O Bank Configuration & Supported Standards

The XC3S400-5TQG144C supports a wide range of I/O signaling standards across its I/O banks, providing maximum design flexibility.

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XC3S400-5TQG144C Speed Grade -5: Performance Advantages

The -5 speed grade is the fastest offering in the Spartan-3 family for this device. Compared to the -4 grade, the -5 variant provides reduced propagation delays and higher maximum clock frequencies — critical for timing-sensitive applications.

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Configuration Modes

The XC3S400-5TQG144C supports multiple configuration methods to match different system architectures:

Xilinx recommends using Platform Flash XL or third-party SPI Flash devices for production configuration.

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Typical Applications of the XC3S400-5TQG144C

The XC3S400-5TQG144C is a versatile device suited for a broad range of embedded and digital design applications:

• Embedded Processing – Implement soft-core processors (e.g., MicroBlaze, PicoBlaze) for embedded control
• Digital Signal Processing (DSP) – Leverage dedicated multipliers for FIR/IIR filters, FFT, and audio processing
• Communications Interfaces – Build UART, SPI, I2C, Ethernet MAC, and CAN controllers
• Motor Control – PWM generation, encoder decoding, and PID control loops
• Image & Video Processing – Line buffering, pixel processing, and frame synchronization
• Industrial Automation – Custom I/O expansion and protocol bridging
• Consumer Electronics – Display controllers, USB interfaces, and multimedia logic
• Prototyping & Development – Rapid hardware prototyping and algorithm acceleration

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XC3S400-5TQG144C vs. Related Spartan-3 Variants

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Design Tools & Software Support

The XC3S400-5TQG144C is supported by Xilinx ISE Design Suite (the legacy tool for Spartan-3 series). Key tools include:

Note: Xilinx ISE is a mature, stable toolchain available as a free download for Spartan-3 family devices.

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Ordering Information

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Frequently Asked Questions (FAQ)

Q: What is the difference between XC3S400-4TQG144C and XC3S400-5TQG144C?
The only difference is the speed grade. The -5 variant offers faster propagation delays and higher achievable clock frequencies compared to the -4 grade, making it preferable for timing-critical designs.

Q: Is the XC3S400-5TQG144C still in production?
The Spartan-3 family has reached end-of-life announcement from Xilinx/AMD, but inventory remains available through authorized distributors. Engineers are encouraged to evaluate migration paths to Spartan-6 or Artix-7 families for new designs.

Q: What programming tool is used for the XC3S400-5TQG144C?
Xilinx ISE Design Suite (version 14.7 is the final release) is the primary tool. JTAG-based programming is performed using the iMPACT utility.

Q: Can the XC3S400-5TQG144C run a soft-core processor?
Yes. The PicoBlaze (8-bit) and MicroBlaze (32-bit) soft-core processors from Xilinx are both supported on Spartan-3 devices, subject to available logic resources.

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Summary

The XC3S400-5TQG144C is a proven, cost-effective FPGA from the Xilinx Spartan-3 family, offering 400,000 system gates, 97 user I/Os, 20 dedicated multipliers, 288 Kb block RAM, and 4 DCMs in a 144-pin TQFP package. Its -5 speed grade makes it one of the fastest options in this series, suitable for demanding timing requirements. Whether used for embedded processing, DSP, communications, or prototyping, this device remains a reliable choice for commercial-temperature applications.