XC3S400-4FG456I - 400K Gate Industrial Spartan-3 FPGA | AMD
MPN: XC3S400-4FG456I ✗ End of LifeXC3S400-4FG456I Overview
A field-programmable gate array, or FPGA, is a reconfigurable digital semiconductor that combines programmable logic, flip-flops, memory blocks, and programmable I/O in one device. An FPGA belongs to the broader semiconductor and programmable-logic hierarchy. Unlike a fixed-function application-specific integrated circuit, an FPGA can be reprogrammed during development to implement control logic, interfaces, signal processing, and system functions without changing the printed circuit board.
The Spartan-3 architecture provides substantial parallelism for cost-sensitive embedded systems. The XC3S400-4FG456I provides 400,000 system gates and 8,064 logic cells, allowing multiple datapaths, state machines, protocol engines, and control blocks to operate concurrently. Its 264 user I/Os support connections to external memory, converters, transceivers, and display or industrial peripherals. The 456-ball FBGA also provides a high pin count for designs requiring substantial parallel connectivity.
Operating from a 1.14 V to 1.26 V core supply, the device is designed for low-voltage digital logic implementations. The 90 nm process generation balances programmable capacity with moderate system cost. This architecture is useful where fixed logic would be inflexible, where product variants require field updates, or where parallel hardware processing provides lower latency than a microcontroller-based software implementation.
Typical applications include industrial control, telecommunications interface equipment, embedded video processing, instrumentation, data acquisition, and communication infrastructure. The 264 I/O count is particularly useful for parallel sensor acquisition and external bus interfaces, while the programmable logic can implement filters, protocol conversion, clocking, and real-time control functions. Existing Spartan-3 intellectual property can also support designs requiring established hardware interfaces.
PCB design must address the fine-pitch BGA routing and power requirements carefully. Follow the Spartan-3 pinout, ball map, recommended decoupling, and PCB-layout guidance in the manufacturer datasheet. Confirm configuration pin states, clocking topology, bank supply requirements, and I/O standards before fabrication because these constraints determine whether a new board can be assembled and operated reliably.
This page combines the manufacturer-family documentation with package, logic-capacity, I/O, temperature, application, and migration guidance. It also distinguishes verified same-package alternatives from broader FPGA upgrade paths that require board redesign, helping engineers assess replacement options without overlooking configuration, timing, and pin-compatibility constraints.
Drop-in alternatives for XC3S400-4FG456I — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
XC3S400-4FGG456I
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
XC3S400-4FGG456C
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
XC3S400-5FGG456I
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
XC3S400-5FGG456C
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
XC3S400A-4FGG456C
✅ Drop-In📋 Reference alternative (not in catalog)
XC3S400-4FG456I Maximum Ratings & Electrical Characteristics
| Device Type | Spartan-3 field-programmable gate array |
| System Gates | 400,000 gates |
| Logic Cells | 8,064 cells |
| User I/O Count | 264 I/Os |
| Number of Package Balls | 456 balls |
| Package | 456-ball FBGA |
| Package Type | Fine-Pitch Ball Grid Array |
| Process Technology | 90 nm |
| Core Supply Voltage Range | 1.14 V to 1.26 V |
| Nominal Core Voltage | 1.2 V |
| Performance Grade | -4 speed grade |
| Temperature Grade | Industrial |
| Junction Temperature Range | -40°C to +100°C |
| Logic Block Count | 294,912 logic cells |
| Mounting Type | Surface Mount |
XC3S400-4FG456I fine-pitch ball grid array Pin Configuration Guide
Pin configuration for XC3S400-4FG456I (fine-pitch ball grid array package). This digital IC includes GPIO, communication interfaces (UART, SPI, I2C), and power pins. Refer to the manufacturer datasheet for alternate pin functions and configuration options. Essential for embedded system design and PCB layout.
No detailed pinout data available for XC3S400-4FG456I.
Refer to the datasheet for full pin configuration.
Typical Applications
XC3S400-4FG456I is suitable for 6 applications: Industrial PLC and Machine Control, Telecommunications Interface Equipment, Data Acquisition and Instrumentation, Embedded Video Processing, Communications Security and Protocol Conversion, Legacy Test and Measurement Systems.
Industrial PLC and Machine Control
The AMD XC3S400-4FG456I fits industrial programmable-logic controller and machine-control systems because it combines 400,000 system gates, 8,064 logic cells, and 264 user I/Os in one device. Engineers can parallelize discrete I/O, sequencers, interlocks, counters, and safety-independent control functions while retaining an industrial -40°C to +100°C junction rating. Its 264 I/Os can connect encoders, sensors, solenoid drivers, relay interfaces, and human-machine interfaces without requiring a high-pin-count microcontroller. The 90 nm Spartan-3 implementation also offers a practical balance of programmable capacity and legacy-device availability. Final design work should verify bank supply voltages, I/O standards, clocking, configuration pins, and timing against the AMD DS099 documentation.
Recommended
Telecommunications Interface Equipment
The XC3S400-4FG456I is suitable for telecommunications interface equipment requiring parallel data movement, protocol control, and numerous external connections. Its 8,064 logic cells can implement channelization, framing logic, byte alignment, switching control, error monitoring, and test sequences, while 264 I/Os provide direct access to backplane transceivers, line cards, and status interfaces. The industrial temperature range supports controlled indoor telecom environments where temperature changes may exceed consumer-device limits. Designers can implement clock-domain relationships and dedicated logic in parallel instead of relying entirely on sequential microcontroller code. A production design should confirm supported memory resources, configuration mode, I/O voltage classes, clock jitter tolerance, and board-level signal integrity, particularly for high-speed links adjacent to the fine-pitch FBGA.
Recommended
Data Acquisition and Instrumentation
The AMD XC3S400-4FG456I can implement parallel data-acquisition, digital signal-conditioning, and instrumentation logic because its programmable fabric supports concurrent sampling paths and control pipelines. The 264 user I/Os allow multiple converters, sensors, counters, and capture memories to be connected, while 8,064 logic cells can perform triggering, channel selection, calibration tables, digital filtering, and interface conversion. A fixed pipeline may provide deterministic response without the overhead of repeated software-driven I/O transactions. For precision measurements, separate analog and digital grounds, route clocks carefully, and use the manufacturer's bank and package guidance to avoid introducing noise or timing skew. The device's 1.14 V to 1.26 V core range and industrial temperature grade suit instrument-control and test-system modules requiring extended operation.
Recommended
Embedded Video Processing
The XC3S400-4FG456I is applicable to embedded video systems that need parallel pixel processing, timing generation, and programmable control around one FPGA. Its 8,064 logic cells can support pixel pipelines, color-space conversion, thresholding, overlay generation, and interface timing, while 264 I/Os provide connectivity to image sensors, frame buffers, and display controllers. Parallel hardware execution can reduce processing latency and make pipeline behavior more deterministic than software-only processing. The 456-ball FBGA also offers more connectivity than a smaller FPGA package, although it increases PCB complexity because escape routing and via-in-pad or microvia strategies must be designed carefully. Engineers should establish video timing, memory interfaces, clock domains, and I/O standards early, then validate them against the DS099 device documentation and simulation results before fabrication.
Recommended
Communications Security and Protocol Conversion
The AMD XC3S400-4FG456I can serve as a protocol-conversion, framing, encryption-interface, or security-control device in communication equipment. Parallel programmable blocks can transform serial and parallel data formats, calculate checksums, manage buffers, and coordinate control messages while exposing status and configuration signals through its 264 I/Os. Its 400,000 system gates provide room for concurrent datapaths rather than a single narrowly defined serial function. The legacy architecture is particularly relevant when an established Spartan-3 design must be maintained rather than redesigned around a newer FPGA family. Secure implementations still require a defined trust boundary, external nonvolatile storage where appropriate, controlled boot or configuration behavior, and careful validation of clocks and power sequencing. The exact memory interfaces and configuration method must be verified for the selected board revision.
Recommended
Legacy Test and Measurement Systems
The XC3S400-4FG456I can serve as the central pattern-generation, sequencing, and timing-control element in a legacy test-and-measurement system. Its 8,064 logic cells allow multiple digital patterns, counters, timing relationships, and acquisition channels to run concurrently, while 264 I/Os provide broad connectivity to fixtures, instruments, and programmable sources. Parallel programmable logic can implement deterministic stimulus generation and response analysis without loading a general-purpose processor with every pin update. The industrial temperature rating supports instrument modules operating across extended internal temperature ranges. However, maintaining a high-pin-count FBGA design requires disciplined layer planning, decoupling, test-point access, and configuration recovery. Engineers should consult the package drawings and pin tables for boundary scan, configuration pins, dedicated inputs, and any pins that become unavailable on the assembled board.
Recommended
Recommended Products Summary
Engineering reference data for XC3S400-4FG456I — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | XC3S400-4FGG456I | XC3S400-4FGG456C | XC3S400-5FGG456I | XC3S400-5FGG456C | XC3S400A-4FGG456C |
|---|---|---|---|---|---|---|
| Package | 456-ball FBGA | 456-ball FBGA | 456-ball FBGA | 456-ball FBGA | 456-ball FBGA | 456-ball FBGA |
| Brand | AMD | AMD | AMD | AMD | AMD | AMD |
| FPGA Family | Spartan-3 | Spartan-3 | Spartan-3 | Spartan-3 | Spartan-3 | Spartan-3A |
| Speed Grade | -4 | -4 | -4 | -5 | -5 | -4 |
| Temperature Grade | Industrial, -40°C to +100°C junction | Industrial | Commercial | Industrial | Commercial | Commercial |
Key Differentiators
- Higher performance-grade option within the same 456-ball package (vs XC3S400-4FGG456I)
- Industrial temperature coverage retained (vs XC3S400-4FGG456C)
- Directly documented package-compatible migration family (vs XC3S400A-4FGG456C)
- High user-I/O density for control and instrumentation (vs XC3S400-4FT256I)
Design Notes
Treat the 456-ball FBGA as a demanding fine-pitch assembly. Follow the official package drawing, recommended PCB stack-up, via rules, solder-mask clearance, and footprint dimensions rather than deriving the land pattern from ball spacing alone. Plan power and ground distribution with lower-impedance paths, use appropriate escape-routing vias, and verify assembly capability with the fabricator before releasing the board.
Assign supply pins by bank and follow the AMD decoupling recommendations for core and I/O supplies. Check voltage tolerances, sequencing, current limits, and startup behavior for every external regulator. Keep sensitive clock and configuration paths away from noisy switching nodes, and include test points that permit checking supply rails and configuration behavior without redesigning the PCB.
Do not approve a replacement solely because its order code contains 456. Compare the official ball maps, power pins, configuration pins, dedicated inputs, I/O standards, supported memory resources, and timing specifications. The XC3S400A-4FGG456C is a package-compatible migration path, but a Spartan-3A design may still require bitstream, constraint, timing, and software-tool updates.
Create a complete clock and I/O budget before routing. Define each clock source, buffer type, target frequency, impedance, topology, and allowable jitter, then confirm that every high-speed interface uses a legal I/O standard and voltage class. Simulate difficult routes and keep return paths continuous across layer transitions. Configuration pins and dedicated pins must also be constrained so accidental states cannot prevent reliable startup.
Compliance Information
The AMD Spartan-3 family documentation identifies the device and its industrial temperature option. No explicit RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals declaration was identified for this ordering code.
