Overview of XA3S400A-4FTG256Q Automotive FPGA
The XA3S400A-4FTG256Q is a high-performance, automotive-qualified Field Programmable Gate Array (FPGA) from AMD’s (formerly Xilinx) XA Spartan-3A Automotive family. Designed specifically for harsh automotive environments, this FPGA delivers exceptional reliability, performance, and flexibility for advanced driver assistance systems (ADAS), infotainment modules, and safety-critical applications. With AEC-Q100 qualification and comprehensive PPAP documentation support, the XA3S400A-4FTG256Q meets the stringent demands of modern automotive electronics.
This automotive FPGA combines 400,000 system gates with 8,064 logic cells in a compact 256-ball FTBGA package, making it an ideal solution for space-constrained automotive designs requiring robust programmable logic capabilities.
Key Technical Specifications
Core Architecture Features
| Specification |
Value |
| Device Family |
XA Spartan-3A Automotive |
| System Gates |
400,000 |
| Logic Cells |
8,064 |
| CLB Array |
40 rows × 24 columns (896 CLBs) |
| Total Slices |
3,584 |
| Distributed RAM |
56 Kb |
| Block RAM |
360 Kb (20 blocks × 18 Kb) |
| Dedicated Multipliers |
20 (18×18-bit) |
| Digital Clock Managers (DCMs) |
4 |
I/O and Package Details
| Feature |
Specification |
| Package Type |
256-ball FTBGA (Fine-pitch Ball Grid Array) |
| Ball Pitch |
1.0 mm |
| Maximum User I/O |
195 pins |
| Maximum Differential I/O Pairs |
90 |
| Speed Grade |
-4 (Standard) |
| Temperature Grade |
Q-Grade (Extended: -40°C to +125°C TJ) |
Power and Performance
| Parameter |
Specification |
| Core Voltage (VCCINT) |
1.2V |
| I/O Voltage (VCCO) |
1.2V to 3.3V (bank-dependent) |
| Auxiliary Voltage (VCCAUX) |
2.5V |
| Process Technology |
90nm CMOS |
| Maximum Operating Frequency |
Up to 667 MHz (internal logic) |
| Data Transfer Rate |
622 Mb/s per I/O |
Advanced Features and Capabilities
Automotive Qualification and Reliability
The XA3S400A-4FTG256Q is fully AEC-Q100 qualified, ensuring it meets automotive industry standards for:
- Extended temperature operation (-40°C to +125°C junction temperature)
- High reliability and long-term automotive-grade performance
- Production Part Approval Process (PPAP) documentation availability
- Stress testing and qualification for automotive environments
SelectIO™ Technology
This automotive Xilinx FPGA supports comprehensive I/O signaling standards:
Single-Ended Standards
- LVCMOS (1.2V, 1.5V, 1.8V, 2.5V, 3.3V)
- LVTTL
- HSTL (Class I, II, III, IV)
- SSTL (Class I, II)
- PCI at 33 MHz and 66 MHz
Differential Standards
- LVDS (Low-Voltage Differential Signaling)
- RSDS
- Mini-LVDS
- PPDS
- BLVDS
- ULVDS
- LDT
Configuration Options
The XA3S400A-4FTG256Q supports multiple flexible configuration modes:
- Master Serial Mode – FPGA controls configuration from SPI Flash
- Master Parallel Mode – Fast configuration from parallel Flash
- Slave Serial Mode – External controller manages configuration
- Slave Parallel Mode – High-speed configuration interface
- JTAG Mode – Development and debugging interface
Unique Device DNA
Each XA3S400A-4FTG256Q contains a factory-programmed, unique Device DNA identifier – a 57-bit code useful for:
- Anti-counterfeiting measures
- Hardware tracking and asset management
- License management in automotive systems
- Supply chain verification
Application Areas
Automotive Electronics
The XA3S400A-4FTG256Q excels in demanding automotive applications:
| Application Category |
Specific Uses |
| Driver Assistance Systems |
Lane departure warning, blind spot detection, parking assist, adaptive cruise control |
| Infotainment Systems |
Media processing, display controllers, audio/video interfaces, connectivity modules |
| Instrument Clusters |
Digital dashboard controllers, gauge clusters, multi-display management |
| Body Electronics |
Lighting control, door modules, climate control, seat control systems |
| Gateway Modules |
CAN/LIN/FlexRay interfaces, protocol conversion, network management |
| Safety Systems |
Airbag control, brake systems support, steering control interfaces |
Industrial and Embedded Systems
Beyond automotive applications, this FPGA serves:
- Industrial automation and control systems
- Motor control and drive systems
- Sensor fusion and data acquisition
- Communication protocol bridging
- Embedded vision processing
- Medical device control systems
Design and Development Support
Software Tools
The XA3S400A-4FTG256Q is supported by AMD’s comprehensive development ecosystem:
- Vivado Design Suite – Modern synthesis, implementation, and debugging
- ISE Design Suite – Legacy support for Spartan-3A family
- IP Core Libraries – Pre-verified intellectual property blocks
- Simulation Tools – Timing analysis and verification
Memory and Processing Resources
Block RAM Configuration
The 360 Kb of block RAM can be configured as:
- True dual-port RAM
- Single-port RAM
- ROM (Read-Only Memory)
- FIFO buffers
- Variable width/depth configurations (up to 18 Kb × 1 to 512 × 36)
DSP Capabilities
The 20 dedicated 18×18-bit multipliers enable:
- High-speed digital signal processing
- MAC (Multiply-Accumulate) operations
- Filter implementations (FIR, IIR)
- Fast Fourier Transform (FFT) processing
- Image and video processing algorithms
Clock Management
Four Digital Clock Managers (DCMs) provide advanced clocking features:
- Clock frequency synthesis and multiplication
- Phase shifting and alignment
- Duty cycle correction
- Clock skew elimination
- Jitter reduction
Competitive Advantages
Why Choose XA3S400A-4FTG256Q?
| Advantage |
Benefit |
| Automotive-Grade Quality |
AEC-Q100 qualified for harsh environments |
| Cost-Effective |
Lower cost per I/O compared to higher-end FPGAs |
| Proven 90nm Technology |
Mature, reliable manufacturing process |
| Flexible I/O |
195 user I/Os with multiple voltage standards |
| Rich Memory Resources |
360 Kb block RAM + 56 Kb distributed RAM |
| Field Upgradeable |
Reconfigurable unlike ASICs – enables updates and fixes |
| Low Development Risk |
No mask costs, shorter time-to-market versus ASICs |
FPGA vs. ASIC Comparison
The XA3S400A-4FTG256Q offers significant advantages over custom ASICs:
- No NRE Costs – Eliminate expensive mask set investments
- Faster Time-to-Market – Reduce development cycles from months to weeks
- Design Flexibility – Modify functionality post-deployment
- Lower Risk – Test and validate before production commitment
- Scalability – Upgrade to larger devices in same family as needed
Package and Pinout Information
FTBGA-256 Package Details
The fine-pitch ball grid array (FTBGA) package offers:
- Compact Footprint – 17mm × 17mm body size
- 1.0mm Ball Pitch – High-density interconnect
- Lead-Free – RoHS compliant (Pb-free)
- Improved Thermal Performance – Better heat dissipation than QFP
- Enhanced Signal Integrity – Shorter bond wires, reduced inductance
Pin Categories
| Pin Type |
Quantity |
Description |
| User I/O |
173 |
Configurable input/output pins |
| Input-Only |
22 |
Dedicated input pins |
| Power (VCCINT) |
Multiple |
1.2V core power supply |
| I/O Power (VCCO) |
Multiple |
Bank-dependent I/O voltage |
| Auxiliary (VCCAUX) |
Multiple |
2.5V auxiliary circuits |
| Ground (GND) |
Multiple |
Ground connections |
Power Management
Supply Voltage Requirements
The XA3S400A-4FTG256Q uses three independent power rails:
- VCCINT (1.2V) – Powers internal logic and configuration memory
- VCCO (1.2V to 3.3V) – Powers I/O banks (voltage varies by bank)
- VCCAUX (2.5V) – Powers auxiliary circuits including DCMs and DLLs
Power-On Sequencing
For optimal operation and lowest power consumption:
- Power rails can be applied in any order
- Recommended: Apply VCCINT last for minimum overall power
- Ensure proper ramp rates per datasheet specifications
- All supplies must reach operating voltage within specification
Ordering Information
Part Number Breakdown: XA3S400A-4FTG256Q
- XA – Automotive grade (AEC-Q100 qualified)
- 3S400A – Spartan-3A, 400K gates
- -4 – Speed grade (standard performance)
- FT – Fine-pitch ball grid array package
- G256 – 256-ball count
- Q – Q-Grade temperature (-40°C to +125°C TJ)
Available Temperature Grades
| Grade |
Temperature Range |
Typical Applications |
| Q-Grade |
-40°C to +125°C TJ |
Engine compartment, under-hood, outdoor modules |
| I-Grade |
-40°C to +100°C TJ |
Passenger compartment, mild environmental conditions |
Environmental and Regulatory Compliance
The XA3S400A-4FTG256Q meets global environmental and safety standards:
- RoHS Compliant – Lead-free, environmentally responsible
- REACH Compliant – European chemical safety regulations
- AEC-Q100 – Automotive Electronics Council qualification
- ECCN Classification – EAR99 (standard export classification)
- Moisture Sensitivity – MSL 3 (168 hours at 30°C/60% RH)
Technical Documentation
Available Resources
Complete technical documentation supports design activities:
- DS681 Datasheet – Full electrical and timing specifications
- UG331 User Guide – Spartan-3 Generation configuration guide
- Packaging Drawings – Mechanical dimensions and footprints
- IBIS Models – Signal integrity simulation
- Timing Models – Speed files for static timing analysis
- Application Notes – Design guidelines and best practices
Comparison with Related Devices
XA Spartan-3A Family Comparison
| Device |
System Gates |
Logic Cells |
Block RAM |
User I/O |
Multipliers |
| XA3S200A |
200K |
4,032 |
288 Kb |
195 |
16 |
| XA3S400A |
400K |
8,064 |
360 Kb |
311 |
20 |
| XA3S700A |
700K |
13,248 |
360 Kb |
372 |
20 |
| XA3S1400A |
1400K |
25,344 |
576 Kb |
375 |
32 |
The XA3S400A-4FTG256Q offers excellent balance between logic density, I/O count, and cost for mid-range automotive applications.
Frequently Asked Questions
What makes this FPGA automotive-grade?
The XA3S400A-4FTG256Q is AEC-Q100 qualified, meaning it has passed rigorous automotive industry testing for temperature cycling, humidity resistance, mechanical shock, and long-term reliability specific to automotive environments.
Can I use commercial Spartan-3A tools?
Yes, the XA3S400A-4FTG256Q uses the same development tools as commercial Spartan-3A devices, including ISE Design Suite and select Vivado features, simplifying migration between automotive and commercial designs.
What configuration memory is recommended?
AMD recommends SPI Flash memory devices (such as Platform Flash or third-party SPI Flash) for automotive applications due to their reliability, cost-effectiveness, and automotive-grade availability.
How does this compare to newer FPGA families?
While newer families offer higher performance, the XA3S400A provides proven 90nm technology with automotive qualification, extensive field deployment history, and competitive pricing for cost-sensitive automotive applications not requiring cutting-edge performance.
What development boards are available?
While AMD doesn’t offer specific automotive development boards for this device, the commercial Spartan-3A Starter Kit can be used for initial development with appropriate voltage and thermal considerations.
Conclusion
The XA3S400A-4FTG256Q represents an optimal solution for automotive electronics designers seeking reliable, qualified, and cost-effective programmable logic. With comprehensive automotive qualification, flexible I/O capabilities, substantial logic and memory resources, and proven field reliability, this FPGA enables innovation in next-generation automotive systems while meeting stringent quality and safety requirements.
Whether implementing advanced driver assistance systems, sophisticated infotainment platforms, or safety-critical control modules, the XA3S400A-4FTG256Q delivers the performance, reliability, and flexibility that automotive applications demand.
For current availability, pricing, and technical support, consult authorized AMD/Xilinx distributors or visit the official AMD Adaptive Computing documentation portal.
