XC3S50A-4FT256I - Spartan-3A 256-LBGA FPGA | AMD
MPN: XC3S50A-4FT256I ✗ End of LifeXC3S50A-4FT256I Overview
A field-programmable gate array is a semiconductor whose digital configuration is defined after fabrication. The FPGA category sits above programmable logic devices and below configurable digital system components, combining configurable logic blocks, programmable I/O, and dedicated resources in one integrated circuit. This hierarchy allows engineers to implement control, communications, data acquisition, signal processing, and interface logic on hardware that can be revised without changing the printed circuit board.
The Spartan-3A family provides configurable logic blocks containing lookup tables and flip-flops, along with programmable general-purpose I/O and dedicated multiplier and accumulator resources in DSP48A slices. Those DSP48A resources are useful for multiply-accumulate operations, while the 144-I/O configuration supports systems with substantial external bus and control connectivity. The exact switching, timing, configuration-memory, and electrical limits must be confirmed in the AMD DS529 Spartan-3A family data sheet before a design is released.
The XC3S50A-4FT256I is differentiated by its combination of the -4 performance grade, industrial-temperature grading, and 256-ball LBGA package. The industrial marking makes it more appropriate for temperature-controlled factory, telecom, and test equipment than a commercial-temperature alternative. The compact 17 x 17 mm package also supports dense board layouts, although its 256-ball geometry requires careful inspection and assembly planning.
Typical applications include industrial automation, telecommunications, embedded instrumentation, data-acquisition systems, and compact control platforms. In these systems, the FPGA can consolidate parallel interface logic, perform protocol conversion, coordinate control sequencing, or implement DSP pipelines. Pairing it with an external data converter, communications transceiver, and nonvolatile configuration storage can produce a complete embedded processing subsystem.
Designers should treat the 256-LBGA footprint as a demanding assembly constraint. The board should use an appropriate ball pitch and copper-compatible surface finish, while assembly planning must account for inspection, cleaning, placement, and solder-joint verification. Power rails, configuration sequencing, decoupling, clocking, and I/O standards should be designed from the complete AMD datasheet rather than inferred solely from the ordering code.
This page combines verified distributor specifications, package data, and the AMD DS529 family reference with practical considerations that are not visible in a basic distributor listing. It also separates documented facts from parameters that still require schematic-level and board-level verification, helping engineers evaluate the XC3S50A-4FT256I for industrial FPGA designs without relying on assumptions.
Drop-in alternatives for XC3S50A-4FT256I — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with XC3S50A-4FT256I (same form factor and footprint) — differing in Device Type, Logic Cells, Package, Speed Grade.
XC3S50A-4FTG256I
✅ Drop-In📋 Reference alternative (not in catalog)
XC3S50A-5FTG256C
✅ Drop-In📋 Reference alternative (not in catalog)
XC3S50AN-4FT256C
✅ Drop-In📋 Reference alternative (not in catalog)
XC3S50AN-4FT256I
✅ Drop-In📋 Reference alternative (not in catalog)
XC3S50AN-5FTG256C
✅ Drop-In📋 Reference alternative (not in catalog)
XC3S50A-4FT256I Maximum Ratings & Electrical Characteristics
| Device Type | Spartan-3A field-programmable gate array (FPGA) |
| Logic Cells | 1,584 logic cells |
| Gate Count | 55,296 gates |
| User I/O | 144 I/O |
| Speed Grade | -4 performance grade |
| Temperature Grade | Industrial |
| Package Code | FT256 |
| Package | 256-ball LBGA |
| Package Body Size | 17 x 17 mm |
| Package Shape | Square |
| Terminal Type | Ball |
| Number of Terminals | 256 balls |
| Mounting Type | Surface mount |
| Programmable Logic Element | Configurable Logic Blocks with LUTs and flip-flops |
| DSP Resource | DSP48A multiply-accumulate slices |
XC3S50A-4FT256I square Pin Configuration Guide
Pin configuration for XC3S50A-4FT256I (square 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 XC3S50A-4FT256I.
Refer to the datasheet for full pin configuration.
Typical Applications
XC3S50A-4FT256I is suitable for 6 applications: Industrial Automation Controller, Data-Acquisition and Signal Conditioning, Telecommunications Line Interface, Embedded Instrumentation, Test and Measurement Equipment, Communications Protocol Bridge.
Industrial Automation Controller
The XC3S50A-4FT256I fits compact industrial automation controllers because its 1,584 logic cells and 144 I/O can support control logic, sequencing, status monitoring, and multiple peripheral interfaces. The industrial-temperature designation is appropriate for controlled factory equipment where commercial-grade variants are not desirable. A designer can implement timing, interlocks, and communication protocols while using the -4 performance grade for a defined operating point. The 256-LBGA footprint also reduces board area, but the 17 x 17 mm ball-grid geometry requires qualified assembly and inspection. Before deployment, verify numeric temperature limits, supply sequencing, configuration behavior, and I/O standards in the AMD DS529 data sheet.
Recommended
Data-Acquisition and Signal Conditioning
The XC3S50A-4FT256I is suitable for parallel data-acquisition systems requiring programmable timing, digital filtering, channel control, and buffer management. Its 144 I/O provide substantial connectivity to converters and external test equipment, while the 1,584 logic cells allow acquisition sequencing and data movement to be consolidated into one FPGA. The DSP48A resources identified for the Spartan-3A family can accelerate multiply-accumulate operations in filtering or modulation paths. A practical implementation would pair the FPGA with a suitable converter and clock source. Verify converter interface voltage, acquisition latency, clock-jitter tolerance, and input-output timing against the complete DS529 specifications before schematic release.
Recommended
Telecommunications Line Interface
The XC3S50A-4FT256I can support telecommunications line-interface equipment that requires parallel data processing, framing control, status aggregation, and programmable logic. The 144 I/O and 1,584 logic cells allow several digital functions to be consolidated, while DSP48A slices can assist with filtering or arithmetic operations. The industrial-temperature designation is useful in indoor network equipment requiring a wider operating grade than a commercial option. For an actual line-card design, confirm the exact I/O standards, clocking architecture, supply rails, and package pinout. The FPGA should be paired with a transceiver that matches the line signaling requirements and with a clock source capable of meeting the interface's timing budget.
Recommended
Embedded Instrumentation
The XC3S50A-4FT256I is well matched to embedded instrumentation because its configurable logic can implement protocol conversion, measurement sequencing, calibration tables, and control interfaces in a single device. The 144-I/O count supports parallel sensors, displays, converters, and service interfaces without requiring a large external glue-logic footprint. Its industrial grading is advantageous in laboratory and process instruments intended for temperature-controlled environments. A practical implementation can use the FPGA to aggregate converter outputs, apply control functions, and format data for a communications transceiver. Verify the exact numeric temperature range, configuration retention method, I/O voltage tolerances, and timing margins in DS529 before qualification.
Recommended
Test and Measurement Equipment
The XC3S50A-4FT256I can implement control, pattern generation, acquisition sequencing, and interface logic in compact test-and-measurement instruments. Its 1,584 logic cells and 144 I/O provide a practical balance for coordinating parallel test channels, instrument buses, status indicators, and timing-sensitive logic. The -4 performance grade offers a defined speed option within the Spartan-3A family, while industrial grading supports equipment deployed in controlled industrial laboratories. For production test systems, use the FPGA alongside a clock generator and suitable communications transceivers. Validate setup-and-hold requirements, configuration startup, power sequencing, and package-level signal integrity against the AMD timing specifications before hardware release.
Recommended
Communications Protocol Bridge
The XC3S50A-4FT256I is applicable to protocol-bridge designs that translate between parallel and serial interfaces, implement framing, perform buffering, or combine multiple control functions. The 144 I/O can connect to parallel bus devices, while programmable logic and DSP48A resources can support byte manipulation and word-level arithmetic. Its industrial-grade ordering code is advantageous for network appliances, factory gateways, and embedded communications equipment. The design should use a transceiver appropriate to each physical layer and maintain deterministic clocking across both sides of the bridge. Confirm configuration compatibility, supported I/O standards, power sequencing, and signal-integrity margins in DS529, and verify the selected alternative's suffix-specific ordering details before substitution.
Recommended
Recommended Products Summary
Engineering reference data for XC3S50A-4FT256I — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | XC3S50A-4FTG256I | XC3S50A-5FTG256C | XC3S50AN-4FT256C | XC3S50AN-4FT256I | XC3S50AN-5FTG256C |
|---|---|---|---|---|---|---|
| Package | 256-LBGA (17 x 17 mm) | 256-LBGA - same package class | 256-LBGA - same package class | 256-LBGA - same package class | 256-FTBGA - same package class | 256-LBGA - same package class |
| Brand | AMD | AMD | AMD | AMD | AMD | AMD |
| FPGA Family | Spartan-3A | Spartan-3A | Spartan-3A | Spartan-3AN | Spartan-3AN | Spartan-3AN |
| Speed Grade | -4 | -4 | -5 | -4 | -4 | -5 |
| Temperature Grade | Industrial | Industrial | Commercial | Commercial | Industrial | Commercial |
Key Differentiators
- Preserves the target's -4 grade and industrial-temperature classification (vs XC3S50A-5FTG256C)
- Uses the original Spartan-3A family designation (vs XC3S50AN-4FT256I)
- Matches the closest verified ordering variant (vs XC3S50A-4FTG256I)
Design Notes
Treat the 256-LBGA footprint as a precision assembly constraint. Use the exact FT256 land pattern from the AMD package drawing and verify it against the PCB library rather than duplicating a generic BGA symbol. Preserve the required ball-pitch, solder-mask, paste, and copper-finish specifications, and account for package warpage, inspection access, and cleaning. Also verify that the board's thermal design supports the selected Spartan-3A device without relying on package height for electrical clearance.
Do not derive power rails, decoupling, or sequencing from the ordering code. Use the DS529 DC operating limits, supply-voltage table, and recommended power-supply circuit for the XC3S50A and FT256 package. Programmable FPGA current can vary with device configuration, so design the supplies and copper paths for the worst documented operating condition and verify startup behavior. The supplied excerpts do not provide numeric voltage or current limits, so those values must be obtained before schematic completion.
Assign clocks to package pins that the AMD pinout identifies as suitable for the intended clocking method, and route them on controlled-impedance layers with short return paths. External clock and transceiver outputs must be checked for I/O voltage compatibility, edge-rate requirements, and drive strength. For high-speed interfaces, apply source-series termination, receiver termination, and length matching exactly as specified in the DS529 and relevant interface standards; do not rely on a generic BGA breakout pattern.
The most common substitution mistake is treating XC3S50A, XC3S50AN, -4, -5, FT, FTG, C, and I as interchangeable labels. The verified candidates share a 256-ball package class, but they differ in family suffix, speed grade, and temperature designation. Before approving a replacement, compare the complete AMD ordering table, package pinout, configuration method, timing limits, and qualification notes. A board-level footprint match alone does not prove functional or lifecycle equivalence.
Compliance Information
The supplied excerpts do not contain product-specific RoHS, REACH, AEC-Q100, lead-free, halogen-free, or conflict-minerals statements for this exact ordering code. Compliance must be confirmed using the manufacturer product page, package documentation, or declaration of compliance.
