AMD XC3S400-5FTG256C

Overview

XC3S400-5FTG256C from AMD (formerly Xilinx) is a Spartan-3 FPGA with 400,000 system gates, 17,280 logic cells, and 256-pin Fine-Pitch Thin Quad Flatpack (FTBGA) package. It operates at 500 MHz internal clock speed, supports LVCMOS25/LVCMOS33 I/O standards, and targets low-cost embedded control and interface bridging applications.

For engineers reviewing the XC3S400-5FTG256C datasheet, pinout, applications, or equivalent options, key selection criteria include logic cell count, I/O voltage compatibility, configuration mode support (Master Serial, Slave SelectMAP), and thermal performance in industrial temperature range.

Technical Context

The XC3S400-5FTG256C implements a hierarchical FPGA architecture with configurable logic blocks (CLBs), distributed RAM, block RAM (432 Kbits), and dedicated multipliers. It uses SRAM-based configuration with external SPI PROM or microprocessor loading.

It supports JTAG boundary-scan (IEEE 1149.1), SelectIO technology for mixed-voltage I/O operation up to 320 pins, and Digital Clock Manager (DCM) blocks providing clock doubling, phase shifting, and duty cycle correction.

Key Specifications

Pinout & Package

XC3S400-5FTG256C is housed in a 256-ball Fine-Pitch Thin Ball Grid Array (FTBGA) package with 1.0 mm ball pitch, 17 × 17 array, and exposed thermal pad. Package dimensions are 17 mm × 17 mm × 1.55 mm (height).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar FPGA-based logic implementation applications.

Compared with XC3S400-5FTG256C, XC3S500E-5FG320C offers scalable logic resources in a larger package, while LFE5U-25F-8MG285C replaces volatile configuration with flash-based startup-both require PCB layout changes and toolchain migration.

Availability

XC3S400-5FTG256C is available at Aetrix Electronics and suitable for industrial control systems, video interface modules, and motor drive electronics requiring stable component supply and long-term obsolescence management.

Supply support for XC3S400-5FTG256C 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 continues development and support of the Spartan family for cost-sensitive, high-volume applications.

The Spartan-3 series was designed specifically for mainstream embedded logic replacement, offering balanced performance, I/O flexibility, and low power consumption in commercial and industrial environments.

FAQ

What is the configuration method supported by XC3S400-5FTG256C?

The XC3S400-5FTG256C supports Master Serial (via SPI PROM), Slave SelectMAP (parallel loading from microprocessor), and JTAG modes. Configuration bitstream is loaded into on-chip SRAM, and the DONE pin asserts high upon successful completion. External configuration memory must be compatible with Xilinx's standard PROM families such as XCF02S or platform flash devices.

Does XC3S400-5FTG256C include on-chip memory resources?

Yes, XC3S400-5FTG256C integrates 432 Kbits of block RAM distributed across 16 blocks (each 18 Kbits), plus distributed RAM within CLBs. This enables dual-port memory structures, FIFOs, and small lookup tables without external memory chips-critical for real-time buffering in industrial I/O and encoder interface applications using XC3S400-5FTG256C.

What I/O standards are supported by XC3S400-5FTG256C?

XC3S400-5FTG256C supports LVCMOS25, LVCMOS33, LVTTL, PCI, and HSTL Class I on its SelectIO pins. Each I/O bank is independently powered, allowing mixed-voltage operation-for example, interfacing 3.3 V peripherals and 2.5 V memory on the same XC3S400-5FTG256C device without level shifters.

Is XC3S400-5FTG256C suitable for industrial temperature operation?

No-XC3S400-5FTG256C is rated for 0°C to +85°C (Commercial grade). For extended temperature operation (–40°C to +100°C), engineers should consider the XC3S400-5FTG256I variant, which shares identical logic resources and pinout but is screened and tested across the industrial range.

How many Digital Clock Managers (DCMs) does XC3S400-5FTG256C contain?

XC3S400-5FTG256C contains four fully independent Digital Clock Managers (DCMs). Each provides clock frequency synthesis (up to 2× multiplication), phase shifting (–180° to +180° in 1° steps), and duty cycle correction-enabling precise timing alignment for video pixel clocks, encoder sampling, and multi-domain synchronization in XC3S400-5FTG256C-based designs.