XC3S400-4TQ144I - 400K Gate Industrial Spartan-3 FPGA | AMD
MPN: XC3S400-4TQ144I ✗ End of LifeXC3S400-4TQ144I Overview
A field-programmable gate array is a semiconductor whose digital logic, memory, and I/O behavior are configured after fabrication. In the product hierarchy, an FPGA sits above programmable logic devices and provides parallel combinational logic, sequential logic, block RAM, programmable I/O, and clocking resources. The Spartan-3 architecture is intended for cost-sensitive embedded applications in which designers need configurable hardware without developing a custom ASIC.
Verified product data identifies 400,000 system gates, 8,064 logic cells, 294,912 RAM bits, and 97 user I/Os for XC3S400-4TQ144I. The listed maximum operating frequency is 630 MHz, and the device uses 1.2 V core technology. These resources make it suitable for control logic, communications interfaces, industrial automation, test equipment, embedded signal processing, and general-purpose programmable system functions. The 144-pin package balances external connectivity against board-space requirements.
The -4 performance designation makes this device appropriate for designs that prioritize cost and power efficiency over the fastest available Spartan-3 grade. Its 8,064 logic cells and block RAM can support parallel datapaths, state machines, protocol handling, and control functions. Exact clock-rate, I/O-standard, and timing-budget conclusions should be based on the manufacturer datasheet and the selected I/O implementation rather than inferred solely from the maximum frequency listed by a distributor.
Typical applications include industrial controller logic, data-acquisition front ends, communications bridges, embedded test systems, and compact control platforms. In these systems, the FPGA can implement parallel interfaces and state machines while offloading deterministic tasks from a microcontroller. The 97 available user I/Os are particularly useful for legacy parallel buses, control signals, status indicators, and external memory or peripheral connections.
Designers should verify the exact bank supply voltages, supported I/O standards, configuration method, pinout, and timing constraints in the manufacturer datasheet before layout release. The TQFP package also requires attention to thermal dissipation and lead co-planarity. Configuration storage, clocking, decoupling, and JTAG access must be planned so that the device can be programmed and debugged in production without board rework.
This page combines verified distributor specifications, official-product search results, same-family replacement options, package-level comparison data, and practical design guidance. It distinguishes confirmed parameters from unavailable details instead of filling gaps with assumed values, helping engineers select, compare, source, and implement the XC3S400-4TQ144I with greater confidence.
Drop-in alternatives for XC3S400-4TQ144I — 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 XC3S400-4TQ144I (same form factor and footprint) — differing in Device Type, System Gates, Operating Temperature, Performance Grade, Temperature Grade.
XC3S400-4TQG144I
✅ Drop-In📋 Reference alternative (not in catalog)
XC3S400-5TQ144C
✅ Drop-InContact for price
View Datasheet →XC3S400-5TQG144C
✅ Drop-In📋 Reference alternative (not in catalog)
XC3S400-4TQ144I Maximum Ratings & Electrical Characteristics
| Device Type | Field Programmable Gate Array (FPGA) |
| FPGA Family | Spartan-3 |
| System Gates | 400,000 |
| Logic Cells | 8,064 |
| Embedded RAM | 294,912 bits |
| User I/O Count | 97 |
| Maximum Operating Frequency | 630 MHz |
| Core Supply Voltage | 1.2 V |
| Process Technology | 90 nm |
| Package | 144-pin TQFP |
| Pin Count | 144 pins |
| Mounting Type | Surface Mount |
| Performance Grade | -4 speed grade |
| Temperature Grade | Industrial |
| Logic Array Blocks | 896 LABs |
XC3S400-4TQ144I 144-pin tqfp Pin Configuration Guide
Pin configuration for XC3S400-4TQ144I (144-pin tqfp 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 XC3S400-4TQ144I.
Refer to the datasheet for full pin configuration.
Typical Applications
XC3S400-4TQ144I is suitable for 6 applications: Industrial Automation Controller, Data Acquisition Front End, Communications Protocol Bridge, Embedded Test and Measurement, Video Timing and Control, General-Purpose Programmable Control.
Industrial Automation Controller
XC3S400-4TQ144I fits industrial automation controllers that require deterministic parallel logic, local buffering, and programmable state machines. Its verified 8,064 logic cells can distribute among sequencers, interlocks, and data-processing functions, while 294,912 RAM bits support counters, trace buffers, or communication queues. The 97 user I/Os provide connections for sensors, actuators, and legacy field buses. Place the FPGA beside the controller circuitry and implement the timing-critical functions directly in fabric. The principal benefit is reduced microcontroller workload and deterministic response. Because the supplied records do not confirm every bank voltage or temperature limit, verify those requirements against the manufacturer datasheet before production release.
Recommended
Data Acquisition Front End
XC3S400-4TQ144I can implement the parallel control and buffering logic for a multi-channel data-acquisition front end. The FPGA's 8,064 logic cells support counters, channel multiplexing, timing generators, and interface state machines, while its 294,912 RAM bits can hold measured samples or intermediate results. With 97 user I/Os, a design can connect parallel converters, control lines, and status signals without relying entirely on a microcontroller. The listed 630 MHz maximum operating frequency provides substantial timing margin for parallel operations, although actual converter interface rates must be validated. Keep high-speed routing short and terminate unused inputs according to the manufacturer recommendations.
Recommended
Communications Protocol Bridge
XC3S400-4TQ144I is appropriate for a communications bridge that converts between parallel and serial protocols using programmable logic and block RAM. Its 8,064 logic cells can accommodate framing, CRC processing, FIFO control, and interface adaptation, while 294,912 RAM bits provide packet buffering. The 97 user I/Os support parallel host connections, configuration signals, and multiple physical-layer interfaces. Compared with a fixed-function bridge, the FPGA permits protocol updates without changing the PCB. Timing closure must include the selected I/O standard and clocking arrangement, and configuration storage must be included so the communications function remains deterministic after power-up.
Recommended
Embedded Test and Measurement
XC3S400-4TQ144I can implement compact test and measurement equipment that combines sequencing, pattern generation, response analysis, and data capture. The FPGA's programmable logic resources suit parallel instruments and timing-sensitive digital tests, while the embedded RAM can buffer vectors or captured results. Its 97 I/Os provide flexibility for legacy probes, trigger controls, status LEDs, and external interfaces. A practical design places the TQFP-144 device near short, controlled-length digital routes and uses a stable reference clock for deterministic results. Verify input thresholds, output drive capability, and timing margins from the manufacturer documentation because the supplied distributor summaries do not specify them.
Recommended
Video Timing and Control
XC3S400-4TQ144I can support timing, control, and interface logic in compact video-processing equipment. Its 8,064 logic cells are suitable for horizontal and vertical timing generation, coordinate processing, overlays, and synchronization, while the 294,912 RAM bits can serve small line buffers or control memories. The 97 I/Os allow connection to converters, memory interfaces, and control processors. Using the FPGA instead of a fixed timing generator makes product parameters easier to modify. The design must still comply with the selected interface's pixel-clock timing, voltage requirements, and impedance rules. External video memory bandwidth and synchronization constraints determine whether the available internal resources are sufficient.
Recommended
General-Purpose Programmable Control
XC3S400-4TQ144I is useful as the central programmable controller in an embedded subsystem that needs adaptable logic without a custom ASIC. A designer can allocate the 8,064 logic cells among control state machines, arithmetic pipelines, communication handlers, and fault logic, with 294,912 RAM bits available for local data. The 97 user I/Os support discrete controls and legacy buses, while the -4 speed classification offers a cost-oriented performance option for designs that close timing comfortably. A useful architecture places the FPGA between a host processor and peripheral devices, with a boot or flash configuration path and JTAG access for diagnostics. Firmware and bitstream version control remain essential for long-term maintenance.
Recommended
Recommended Products Summary
Engineering reference data for XC3S400-4TQ144I — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | XC3S400-4TQG144I | XC3S400-5TQ144C | XC3S400-5TQG144C |
|---|---|---|---|---|
| Package | TQFP-144 | TQFP-144 - same package | TQFP-144 - same package | TQFP-144 - same package |
| Brand | AMD | AMD | AMD | AMD |
| FPGA Family | Spartan-3 | Spartan-3 | Spartan-3 | Spartan-3 |
| System Gates | 400,000 | 400,000 | 400,000 | 400,000 |
| Logic Cells | 8,064 | 8,064 | 8,064 | 8,064 |
| Embedded RAM | 294,912 bits | 294,912 bits | 294,912 bits | 294,912 bits |
| User I/O Count | 97 | 97 | 97 | 97 |
| Speed Grade | -4 | -4 - same speed grade | -5 - one speed grade higher | -5 - one speed grade higher |
| Temperature Classification | Industrial | Industrial - same classification | Commercial | Commercial |
| Core Supply Voltage | 1.2 V | 1.2 V | 1.2 V | 1.2 V |
Key Differentiators
- Closest ordering-code alternative preserves the target's electrical classification (vs XC3S400-4TQG144I)
- Higher speed classification offers additional timing margin for constrained designs (vs XC3S400-5TQ144C)
- Target retains industrial classification for temperature-sensitive industrial designs (vs XC3S400-5TQG144C)
Design Notes
Use the official 144-pin TQFP land pattern and verify pin 1 orientation against the manufacturer package drawing. Keep configuration pins, clock inputs, and ground connections consistent with the datasheet recommendations. Because the supplied search data does not include the full pin table, do not release the PCB from a distributor summary alone. Cross-check every power pin against the schematic and use the manufacturer reference schematic as the authority for bypass placement and pin connectivity.
Design the 1.2 V core rail and all I/O-bank supplies separately, following the manufacturer power-supply topology and decoupling guidance. The verified data does not provide bank voltage values, current limits, or capacitor quantities, so those details must come from the manufacturer datasheet. Check total core and I/O current against the selected speed grade and temperature class. Sequence supplies and configuration behavior as specified rather than assuming that all rails can be energized in any order.
Do not treat a same-package FPGA as an automatically interchangeable device. The XC3S400-4TQG144I is close to the target but differs in ordering treatment, while the -5 options change speed and temperature classification. Re-run timing analysis, verify configuration compatibility, review pin-level voltage constraints, and confirm tooling and bitstream support before substitution. For LCMXO2-4000HC-4TG144I, do not attempt a production drop-in change because its verified 4,320 logic cells and 115 I/Os differ materially from the target's 8,064 cells and 97 I/Os.
Route clock and high-speed interface signals according to the selected I/O standard, with attention to trace length, reference planes, impedance, and return paths. The listed 630 MHz maximum operating frequency is not a guarantee for every I/O or pin arrangement. Use the manufacturer's timing and I/O guidance to evaluate each interface, and avoid relying on general FPGA assumptions when migrating between speed grades. JTAG and configuration routing should also be checked for reliable programming and production test access.
Compliance Information
The supplied product results do not provide verifiable compliance statements for RoHS, REACH, AEC-Q100, lead-free status, halogen-free status, or conflict minerals. The G suffix in XC3S400-4TQG144I should not be interpreted as verified RoHS or lead-free compliance without the manufacturer ordering information. AEC-Q100 is not applicable because this is an FPGA rather than an automotive-qualified device, and no automotive qualification claim appears in the supplied data.
