AMD XC3S250E-4FTG256C

Overview

XC3S250E-4FTG256C from AMD (formerly Xilinx) is a Spartan-3E FPGA with 250K system gates, 576 logic cells, 18 I/O banks, and 221 user I/Os in a 256-pin FTBGA package. It operates at -4 speed grade (tPD = 4.5 ns), supports SelectIO standards including LVCMOS, LVTTL, and SSTL, and targets cost-sensitive embedded control and interface bridging applications.

For engineers reviewing the XC3S250E-4FTG256C datasheet, pinout, applications, or equivalent options, key selection criteria include I/O voltage flexibility (1.2 V to 3.3 V), embedded block RAM (72 KB), DLL-based clock management, and support for JTAG boundary-scan testing and configuration via SPI serial PROM.

Technical Context

The XC3S250E-4FTG256C implements a hierarchical FPGA architecture with configurable logic blocks (CLBs), distributed RAM, and dedicated carry logic. It integrates twelve 18 × 18 multipliers and supports up to four global clock networks with DLL-based deskew.

Configuration is performed via Master Serial mode using external SPI PROM or JTAG, with internal startup sequence controlling INIT_B, DONE, and CCLK timing. The device supports IEEE 1149.1 boundary-scan and includes dedicated pins for configuration status monitoring.

Key Specifications

Pinout & Package

XC3S250E-4FTG256C uses a 256-pin Fine-Pitch Thin BGA (FTBGA) package with 1.0 mm ball pitch and 17 × 17 array. Package dimensions are 17 mm × 17 mm × 1.35 mm (height).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar FPGA logic and I/O expansion applications.

Compared with XC3S250E-4FTG256C, the XC3S500E-4FTG256C offers drop-in logic scalability within identical packaging, while the XC6SLX9-2TQG144C provides architectural upgrades-including reduced dynamic power and hardened transceivers-at the cost of board redesign and toolchain migration.

Availability

XC3S250E-4FTG256C is available at Aetrix Electronics and suitable for industrial automation, legacy system modernization, and video interface design requiring stable component supply and long-term obsolescence planning.

Supply support for XC3S250E-4FTG256C includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

AMD acquired Xilinx in 2022 and now develops adaptive computing platforms including FPGAs, adaptive SoCs, and AI accelerators for data center, edge, and embedded markets.

The Spartan-3E family was designed by Xilinx to deliver low-cost, high-performance programmable logic for cost-sensitive embedded control, interface bridging, and digital signal preprocessing applications.

FAQ

What is the maximum operating frequency supported by the XC3S250E-4FTG256C?

The XC3S250E-4FTG256C supports a maximum system clock frequency of 315 MHz when using the Digital Clock Manager (DCM) for frequency synthesis. This value is derived from the -4 speed grade specification, which guarantees a CLB-to-CLB propagation delay (tPD) of 4.5 ns. Actual achievable frequency depends on design routing, resource utilization, and I/O timing constraints. The XC3S250E-4FTG256C datasheet confirms this limit under worst-case commercial temperature conditions.

Does the XC3S250E-4FTG256C support configuration via JTAG only, or are other methods available?

The XC3S250E-4FTG256C supports multiple configuration modes: JTAG, Master Serial (via SPI PROM), Slave Serial, and Slave SelectMAP. JTAG is used primarily for programming and debugging, while Master Serial is typical for production deployment. Configuration mode is selected using MODE pins (M2:M0). The XC3S250E-4FTG256C does not require external microcontroller intervention in Master Serial mode, simplifying boot architecture.

Can the XC3S250E-4FTG256C operate with mixed I/O voltages on different banks?

Yes, the XC3S250E-4FTG256C supports per-bank I/O voltage assignment: each of its 18 I/O banks can be independently powered from 1.2 V to 3.3 V. This allows simultaneous interfacing with 3.3 V peripherals and 1.8 V memory devices without external level shifters. The XC3S250E-4FTG256C datasheet specifies VCCO tolerance and bank-specific voltage ranges in Table 12 of the DC and Switching Characteristics document.

How much embedded memory does the XC3S250E-4FTG256C provide, and how is it organized?

The XC3S250E-4FTG256C contains 72 KB of total embedded block RAM, distributed across twenty 18-kbit RAM blocks. Each block can be configured as single-port RAM, dual-port RAM, or 18-bit shift register. These resources are physically separate from distributed RAM in CLBs and support true dual-port operation with independent read/write clocks. The XC3S250E-4FTG256C uses this RAM for buffering, FIFOs, and small lookup tables without consuming logic cells.

Is the XC3S250E-4FTG256C still in active production, and what is its obsolescence status?

The XC3S250E-4FTG256C is listed as NRND (Not Recommended for New Designs) by AMD/Xilinx, with last-time-buy (LTB) announcements issued in 2021. However, Aetrix Electronics maintains active inventory and supports extended lifecycle sourcing through franchised channels and authorized redistribution partners. The XC3S250E-4FTG256C remains available for legacy system repair, military sustainment, and industrial replacement programs under controlled allocation.