The Xilinx XC3S50AN-4TQG144I is an industrial-temperature variant of the Spartan-3AN FPGA family, combining the features of the Spartan-3A platform with in-system Flash memory for configuration and nonvolatile data storage. Built on 90 nm CMOS technology and operating at a core voltage of 1.2 V, this device eliminates the need for external configuration PROMs while operating reliably across a wide temperature range of –40°C to 100°C. The suffix “I” indicates industrial temperature range, making this device suitable for applications where commercial-grade devices (0°C to 85°C) would be inadequate.

Industrial Temperature Grade

Unlike commercial-grade devices that are specified only from 0°C to 85°C, the XC3S50AN-4TQG144I is characterised for operation from –40°C to 100°C (junction temperature). This extended range is critical for applications in outdoor enclosures, unheated industrial environments, automotive systems (non-engine compartment), telecom outdoor cabinets, and any equipment subject to wide temperature swings. The wider operating range is achieved through more stringent testing and characterisation, ensuring reliable operation under extreme conditions.

Nonvolatile Advantage

The Spartan-3AN family integrates 4 Mb of embedded Flash memory, which stores the FPGA configuration bitstream internally. This eliminates the need for external PROMs, reduces board space, lowers system cost, and enhances design security. The Flash memory can also be used for user data storage, code shadowing, or scratchpad memory in embedded processing applications. The device powers up instantly from the internal Flash, making it suitable for applications where fast configuration is required.

Architecture

The XC3S50AN-4TQG144I features 1,584 logic cells organised into 176 configurable logic blocks (CLBs). The hierarchical SelectRAM memory architecture includes 54 Kbits of block RAM and 11 Kbits of distributed RAM, totalling 55,296 bits of on-chip memory. The device also includes three 18x18 dedicated multipliers for digital signal processing acceleration. Two Digital Clock Managers (DCMs) provide precise clock management capabilities supporting internal logic operation up to 667 MHz and I/O switching up to 250 MHz.

I/O Capabilities

The device provides 108 user I/O pins supporting a wide range of single-ended and differential signalling standards, including LVCMOS, LVTTL, HSTL, SSTL, LVDS, and RSDS. SelectIO technology allows each I/O bank to operate at 3.3V, 2.5V, 1.8V, 1.5V, or 1.2V levels. The I/Os are fully 3.3V tolerant and support hot swap compliance.

Packaging and Environmental

The XC3S50AN-4TQG144I is housed in a 144-pin TQFP (Thin Quad Flat Pack) package measuring 20 x 20 mm with a 0.5 mm pitch. The package is RoHS compliant (ROHS3) and REACH unaffected. Moisture Sensitivity Level is MSL 3, requiring a floor life of 168 hours after opening. The device is supplied in tray packaging.

Development Support

Supported by Xilinx ISE WebPACK and ISE Design Suite (ISE 14.7). The device is not supported by the newer Vivado toolchain. For new designs requiring industrial temperature range and nonvolatile FPGA technology with modern tool support, consider newer device families such as Spartan-7.

Product Status

The XC3S50AN-4TQG144I is marked as obsolete by DigiKey. Stock is limited and the device is no longer in active production. For existing designs, verify supply availability before committing to volume production.