Overview of XA3S500E-4FT256C FPGA
The XA3S500E-4FT256C is a powerful field-programmable gate array (FPGA) from AMD’s (formerly Xilinx) renowned Spartan-3E family, engineered to deliver exceptional performance for cost-sensitive embedded systems and industrial applications. This versatile FPGA combines advanced programmable logic capabilities with integrated features, making it an ideal choice for engineers developing complex digital systems requiring high reliability and flexibility.
As part of the Spartan-3E series, the XA3S500E-4FT256C represents a proven solution for designers seeking a balance between performance, power efficiency, and affordability. Whether you’re developing telecommunications equipment, industrial automation systems, or consumer electronics, this FPGA provides the computational power and I/O flexibility needed for modern digital designs.
Key Technical Specifications
Core Features and Architecture
| Specification |
Value |
| Logic Cells |
10,476 cells |
| System Gates |
500,000 gates |
| Distributed RAM |
73K bits |
| Block RAM |
360 Kb (36,192 bits) |
| User I/O Pins |
190 |
| Maximum Operating Frequency |
572 MHz |
| DSP Slices |
20 slices |
| Technology Node |
90nm CMOS |
| Core Voltage |
1.2V |
| Package Type |
256-pin FTBGA (Fine-Pitch Ball Grid Array) |
| Operating Temperature Range |
-40°C to +100°C (Industrial grade) |
Memory and Processing Capabilities
The XA3S500E-4FT256C features 36,192 bits of block RAM that can be configured as either single-port or dual-port memory, ensuring efficient data storage and retrieval for demanding applications. The inclusion of 20 DSP slices makes this FPGA particularly well-suited for high-speed signal processing tasks, including digital filters, FFT operations, and complex mathematical computations.
Detailed Product Specifications Table
| Category |
Parameter |
Details |
| Device Family |
FPGA Type |
Spartan-3E |
| Manufacturer |
Brand |
AMD (Xilinx) |
| Part Number |
Model |
XA3S500E-4FT256C |
| Logic Resources |
Logic Cells |
10,476 |
|
System Gates |
500,000 |
|
CLBs (Configurable Logic Blocks) |
1,164 |
| Memory |
Block RAM |
360 Kb |
|
Distributed RAM |
73 Kb |
| DSP Resources |
DSP Slices |
20 |
|
18×18 Multipliers |
20 |
| I/O Capabilities |
User I/O Pins |
190 |
|
Maximum I/Os (device) |
232 |
|
Differential I/O Pairs |
92 |
| Clock Management |
DCMs (Digital Clock Managers) |
4 |
|
Global Clock Networks |
24 |
| Physical |
Package |
256-pin FTBGA |
|
Package Dimensions |
17mm x 17mm |
|
Ball Pitch |
1.0mm |
| Power |
Core Voltage (VCCINT) |
1.2V |
|
I/O Voltage (VCCO) |
1.2V to 3.3V |
|
Auxiliary Voltage (VCCAUX) |
2.5V |
| Performance |
Maximum Frequency |
572 MHz |
|
Speed Grade |
-4 (fastest) |
| Temperature |
Operating Range |
-40°C to +100°C |
|
Grade |
Industrial (XA) |
| Standards |
Compliance |
RoHS Compliant (lead-free) |
Advanced Features and Capabilities
Clock Management Resources
The XA3S500E-4FT256C incorporates four Digital Clock Managers (DCMs) that provide sophisticated clock distribution and synchronization capabilities. These DCMs enable clock frequency synthesis, phase shifting, and jitter reduction, which are essential for maintaining timing integrity in high-speed digital designs. The device also features 24 global clock networks that ensure low-skew clock distribution across the entire FPGA fabric.
Programmable I/O Architecture
With 190 user I/O pins, the XA3S500E-4FT256C offers extensive connectivity options for interfacing with various peripheral devices and communication protocols. The I/O banks support multiple voltage standards ranging from 1.2V to 3.3V, providing compatibility with both legacy and modern interface standards. Each I/O pin can be configured individually for different functions, including:
- Single-ended or differential signaling
- Programmable drive strength
- Adjustable slew rates
- Internal pull-up/pull-down resistors
- Input delay compensation
DSP Capabilities
The 20 dedicated DSP slices in the XA3S500E-4FT256C are optimized for mathematical operations commonly used in signal processing applications. Each DSP slice includes an 18×18-bit multiplier and associated arithmetic logic, enabling efficient implementation of:
- Digital signal filtering (FIR, IIR filters)
- Fast Fourier Transform (FFT) algorithms
- Digital communication modulators/demodulators
- Image and video processing pipelines
- Control system algorithms
Application Areas and Use Cases
Industrial Automation and Control
The XA3S500E-4FT256C excels in industrial automation applications where reliability and deterministic performance are paramount. Common implementations include:
- Motor Control Systems: Implementation of advanced motor control algorithms including FOC (Field-Oriented Control) and sensorless control
- PLC Replacements: Flexible logic control systems with faster response times than traditional PLCs
- Machine Vision: Real-time image processing for quality inspection and defect detection
- Industrial Communication: Protocol bridging and conversion (EtherCAT, PROFINET, Modbus)
Telecommunications and Networking
The high-speed I/O capabilities and DSP resources make this FPGA ideal for telecommunications infrastructure:
- Base Station Processing: Channel coding, modulation/demodulation for wireless systems
- Network Packet Processing: High-speed packet filtering and routing
- Protocol Conversion: Interface bridging between different communication standards
- Signal Conditioning: Equalization and error correction in data transmission
Consumer Electronics
The cost-effective nature of the Spartan-3E family makes the XA3S500E-4FT256C suitable for consumer applications:
- Audio/Video Processing: Real-time video encoding/decoding, audio effects processing
- Display Controllers: Custom display timing generators and image enhancement
- Gaming Hardware: Graphics acceleration and custom gaming peripherals
- Smart Home Devices: IoT device controllers with complex logic requirements
Medical Equipment
The industrial temperature range and reliability features support medical device applications:
- Diagnostic Imaging: Signal processing for ultrasound and other imaging modalities
- Patient Monitoring: Real-time signal processing for vital sign monitoring
- Laboratory Instrumentation: Data acquisition and analysis systems
- Therapeutic Equipment: Control systems for medical treatment devices
Performance Characteristics Table
| Performance Metric |
Specification |
Notes |
| Logic Delay |
0.32 ns (typical) |
Internal routing delay |
| Clock-to-Output |
2.7 ns (max) |
I/O buffer delay |
| Setup Time |
1.5 ns (typ) |
Input register timing |
| Maximum Toggle Rate |
420 MHz |
I/O pin switching |
| Power Consumption (Static) |
150 mW (typical) |
No switching activity |
| Power Consumption (Dynamic) |
1.2W (typical) |
At 50% toggle rate |
| Configuration Time |
50 ms (typical) |
Via JTAG interface |
| Configuration Memory |
1.9 Mb |
Bitstream size |
Design Development and Tools
Compatible Development Software
Designing with the XA3S500E-4FT256C requires Xilinx FPGA development tools. The primary design suite is:
- Xilinx ISE Design Suite: The legacy but still widely-used development environment specifically supporting Spartan-3E devices
- XST (Xilinx Synthesis Technology): Optimized synthesis engine for Spartan architectures
- PlanAhead: Floor planning and pin assignment tool
- ChipScope Pro: Integrated logic analyzer for debugging
Programming and Configuration Options
The XA3S500E-4FT256C supports multiple configuration modes:
| Configuration Mode |
Description |
Use Case |
| JTAG |
Industry-standard programming interface |
Development and debugging |
| Master Serial |
FPGA controls external flash memory |
Simple autonomous systems |
| Slave Serial |
External processor loads configuration |
Processor-based systems |
| Master/Slave Parallel |
High-speed configuration |
Fast boot applications |
| BPI (Byte Peripheral Interface) |
Parallel flash interface |
High-reliability systems |
Package and Pin Configuration
FTBGA Package Details
The 256-pin Fine-Pitch Ball Grid Array (FTBGA) package offers several advantages:
- Compact Footprint: 17mm x 17mm package size ideal for space-constrained designs
- Excellent Thermal Performance: Direct die-to-package thermal path enables efficient heat dissipation
- High Signal Integrity: Short bond wire connections reduce inductance and improve signal quality
- Cost-Effective Assembly: Compatible with standard PCB manufacturing processes
Pin Assignment Guidelines
| I/O Bank |
Number of Pins |
Voltage Range |
Typical Applications |
| Bank 0 |
47 I/Os |
1.2V – 3.3V |
General purpose I/O |
| Bank 1 |
48 I/Os |
1.2V – 3.3V |
High-speed interfaces |
| Bank 2 |
47 I/Os |
1.2V – 3.3V |
Communication interfaces |
| Bank 3 |
48 I/Os |
1.2V – 3.3V |
Memory interfaces |
Power Management and Thermal Considerations
Power Supply Requirements
| Power Rail |
Voltage |
Tolerance |
Maximum Current |
Purpose |
| VCCINT |
1.2V |
±5% |
1.5A |
Core logic |
| VCCAUX |
2.5V |
±5% |
350mA |
Auxiliary circuits |
| VCCO |
1.2V – 3.3V |
±5% |
500mA per bank |
I/O buffers |
Thermal Management
The XA3S500E-4FT256C’s thermal characteristics require careful consideration:
- Junction Temperature (Tj max): 125°C
- Typical Power Dissipation: 1.5W at full utilization
- Recommended Heatsink: Required for applications exceeding 1W dissipation
- Thermal Resistance (θJA): 24°C/W (with airflow)
Comparison with Similar FPGAs
| Feature |
XA3S500E-4FT256C |
XC3S400E |
XC3S1000E |
| Logic Cells |
10,476 |
8,064 |
17,280 |
| System Gates |
500K |
400K |
1M |
| Block RAM |
360 Kb |
288 Kb |
504 Kb |
| DSP Slices |
20 |
16 |
24 |
| User I/Os |
190 |
173 |
221 |
| Package Options |
256-FTBGA |
208-PQFP, 240-FBGA |
320-FBGA, 456-FBGA |
| Price Point |
Mid-range |
Lower |
Higher |
Quality and Reliability Features
Industrial-Grade Specifications
The “XA” prefix in XA3S500E-4FT256C designates this as an automotive/industrial-grade component with enhanced reliability features:
- Extended Temperature Range: -40°C to +100°C operation ensures reliability in harsh environments
- Enhanced Screening: Additional testing and burn-in procedures for improved quality
- ESD Protection: Human Body Model (HBM) >2000V, Machine Model >200V
- Latch-up Immunity: >100mA per JESD78 standards
- MTBF (Mean Time Between Failures): >1,000,000 hours at typical operating conditions
Compliance and Certifications
- RoHS Compliant: Lead-free and environmentally friendly
- REACH Compliant: Meets European chemical safety regulations
- Conflict Minerals: Complies with Dodd-Frank Act requirements
- Automotive Grade: Suitable for automotive applications (when properly qualified)
Design Resources and Support
Reference Designs and IP Cores
Engineers working with the XA3S500E-4FT256C have access to extensive resources:
- Xilinx IP Core Library: Pre-verified functional blocks including processors, memory controllers, and communication interfaces
- Reference Designs: Example projects demonstrating common application implementations
- Application Notes: Detailed technical documents covering specific design challenges
- PCB Layout Guidelines: Best practices for board design and signal integrity
Technical Documentation
Essential documentation for XA3S500E-4FT256C development:
- Product Datasheet: Complete electrical and timing specifications
- User Guide: Comprehensive device architecture and feature descriptions
- Packaging and Pinout: Detailed package drawings and pin assignments
- Characterization Reports: Performance data across operating conditions
Ordering Information and Availability
Part Number Breakdown
XA3S500E-4FT256C
- XA: Automotive/Industrial grade
- 3S: Spartan-3 family
- 500E: 500K gate count, Enhanced features
- -4: Speed grade (fastest available)
- FT256: Fine-pitch BGA with 256 pins
- C: Commercial temperature range modifier
Package Marking
The device top marking includes:
- Part number identification
- Date code (manufacturing week/year)
- Lot traceability code
- Country of origin
- AMD/Xilinx logo
Frequently Asked Questions (FAQ)
Q: What is the difference between XA3S500E and XC3S500E? A: The “XA” prefix indicates automotive/industrial grade with enhanced reliability features and extended temperature range, while “XC” is the commercial grade version.
Q: Can I use Vivado Design Suite with this device? A: No, the Spartan-3E family requires the ISE Design Suite. Vivado supports only 7-series and newer Xilinx devices.
Q: What programming cables are compatible? A: Platform Cable USB II, Digilent HS2/HS3, and other JTAG-compatible programmers supporting IEEE 1149.1 standard.
Q: Is the device still in production? A: The XA3S500E-4FT256C is considered mature/legacy but remains available through authorized distributors and specialty suppliers.
Q: What PCB stack-up is recommended? A: A minimum 6-layer board is recommended with dedicated power and ground planes for optimal signal integrity.
Conclusion: Why Choose XA3S500E-4FT256C
The XA3S500E-4FT256C represents an excellent balance of performance, features, and cost-effectiveness for engineers requiring reliable FPGA solutions. Its industrial-grade specifications, proven architecture, and comprehensive development tool support make it a dependable choice for mission-critical applications across telecommunications, industrial automation, medical equipment, and consumer electronics.
With 10,476 logic cells, 360 Kb of block RAM, 20 DSP slices, and 190 user I/O pins housed in a compact 256-pin FTBGA package, this Xilinx FPGA delivers the computational power and flexibility needed for modern digital designs. The extended temperature range and enhanced reliability features ensure long-term operational stability in demanding environments.
Whether you’re upgrading an existing design or starting a new project, the XA3S500E-4FT256C provides a solid foundation for innovation in programmable logic applications. Its mature ecosystem, extensive documentation, and proven track record in fielded applications make it a low-risk choice for production designs requiring longevity and supply chain stability.
