The XC3S50-5PQG208C is a high-performance, cost-effective Field-Programmable Gate Array (FPGA) from Xilinx’s Spartan-3 family. Manufactured on advanced 90nm CMOS process technology, this device delivers 50,000 system gates in a compact 208-pin PQFP package — making it one of the most popular entry-level Xilinx FPGA solutions for commercial and industrial designs.

Whether you are designing embedded control systems, digital signal processing pipelines, or communication interfaces, the XC3S50-5PQG208C offers an excellent balance of logic density, I/O flexibility, and clock management capability at a competitive price point.

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What Is the XC3S50-5PQG208C?

The XC3S50-5PQG208C belongs to the Spartan-3 FPGA family, an eight-member product line specifically engineered for high-volume, cost-sensitive consumer and industrial electronic applications. The “-5” speed grade designates this as the highest-performance variant within the XC3S50 series, operating at up to 725 MHz internal clock frequency.

The “PQG208” in the part number identifies the 208-pin Plastic Quad Flat Pack (PQFP) Pb-free package, and the trailing “C” confirms commercial temperature range operation (0°C to 85°C).

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XC3S50-5PQG208C Key Specifications

Core Device Parameters

Memory Resources

Clock Management

I/O and Package

Electrical and Environmental

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XC3S50-5PQG208C Speed Grade Comparison

The Spartan-3 XC3S50 in the PQG208 package is available in three speed grades. The table below compares them to help you choose the right variant for your design:

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XC3S50-5PQG208C Architecture Overview

Configurable Logic Blocks (CLBs)

The XC3S50-5PQG208C contains 192 Configurable Logic Blocks arranged in a 16×12 array. Each CLB consists of four slices, and each slice contains two 4-input Look-Up Tables (LUTs) and two storage elements (flip-flops or latches). This architecture enables efficient implementation of combinatorial logic, arithmetic functions, and state machines.

Block RAM

The device integrates 4 × 18 Kbit dual-port Block RAM blocks, totaling 72 Kbits of on-chip memory. The dual-port structure allows simultaneous read and write access from two independent buses — ideal for FIFO buffers, lookup tables, and local data storage without consuming distributed LUT resources.

Dedicated Multipliers

Four 18×18-bit dedicated hardware multipliers are embedded alongside the Block RAM. These accelerate DSP operations such as filtering, correlation, and arithmetic without occupying general-purpose CLB resources, significantly boosting multiply-intensive designs.

Digital Clock Managers (DCMs)

Two Digital Clock Managers provide flexible, zero-skew clock distribution. DCMs support frequency synthesis, phase shifting, and duty-cycle correction, enabling reliable clocking across the entire device fabric.

I/O Blocks (IOBs)

The 208-pin PQG package exposes up to 124 user-configurable I/O pins supporting a wide variety of single-ended and differential I/O standards, including LVTTL, LVCMOS (1.2V–3.3V), SSTL, HSTL, LVDS, LVPECL, and more. Digitally Controlled Impedance (DCI) is available on supported banks for on-chip termination.

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Supported I/O Standards

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Configuration Modes

The XC3S50-5PQG208C supports multiple configuration methods, giving designers flexibility in how the FPGA loads its bitstream at power-up:

Configuration data is stored in reprogrammable static CMOS configuration latches (CCLs), making the device infinitely re-programmable during development and in the field.

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Development Tools for XC3S50-5PQG208C

The XC3S50-5PQG208C is supported by the following Xilinx/AMD design tools:

Note: Vivado Design Suite does not support Spartan-3 devices. ISE Design Suite (version 14.7 or later) is recommended for all XC3S50 designs.

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Typical Applications of XC3S50-5PQG208C

The XC3S50-5PQG208C is well-suited for a broad range of embedded and digital design applications:

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Ordering Information & Part Number Decoder

Understanding the XC3S50-5PQG208C part number is straightforward:

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XC3S50-5PQG208C vs. Related Spartan-3 Devices

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Why Choose the XC3S50-5PQG208C?

• Proven architecture: The Spartan-3 family is a mature, battle-tested platform with an extensive ecosystem of reference designs, application notes, and community support.
• High-speed grade: The “-5” speed grade delivers the fastest timing performance available in the XC3S50 lineup, essential for designs with tight setup and hold time margins.
• Lead-free packaging: The “G” suffix confirms RoHS compliance, making this part suitable for products targeting European and global markets.
• Rich I/O flexibility: Support for over 20 single-ended and differential I/O standards in a single device reduces external component count.
• Cost-effective prototyping: At 50K gates, the XC3S50-5PQG208C is ideal for proof-of-concept and low-gate-count production designs without overpaying for unused resources.

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Frequently Asked Questions

Q: What is the difference between XC3S50-5PQG208C and XC3S50-4PQG208C? The only difference is the speed grade. The “-5” variant is the higher-performance version, rated at 725 MHz compared to approximately 630 MHz for the “-4” grade. Both use the same 208-pin Pb-free PQFP package and commercial temperature range.

Q: Is the XC3S50-5PQG208C RoHS compliant? Yes. The “G” in the package code (PQG208) confirms this is a lead-free, RoHS-compliant device.

Q: What programming software is required for XC3S50-5PQG208C? Xilinx ISE Design Suite 14.7 is the recommended tool. Vivado does not support Spartan-3 devices.

Q: What is the core supply voltage? The XC3S50-5PQG208C requires a 1.2V core supply (VCCINT). I/O banks support 1.2V to 3.3V depending on the selected I/O standard.

Q: Can the XC3S50-5PQG208C be used in industrial temperature applications? This “C” (commercial) grade part is rated from 0°C to +85°C. For industrial temperature operation (-40°C to +100°C), use the XC3S50-5PQG208I instead.