AMD XC3S400-5FG320C

Overview

XC3S400-5FG320C from AMD (formerly Xilinx) is a Spartan-3 FPGA with 400,000 system gates, 241 I/O pins, and a 5 ns logic delay grade in a 320-pin Fine-Pitch Ball Grid Array (FBGA) package. It integrates up to 24 embedded multipliers, 1728 configurable logic blocks (CLBs), and supports LVCMOS25/LVCMOS33 I/O standards for digital signal processing and control logic implementation in industrial motion controllers.

For engineers reviewing the XC3S400-5FG320C datasheet, pinout, applications, or equivalent options, key selection criteria include logic resource count, I/O voltage compatibility, maximum system clock frequency (280 MHz), and thermal performance in convection-cooled enclosures.

Technical Context

The XC3S400-5FG320C implements a hierarchical FPGA architecture with configurable logic blocks (CLBs), distributed RAM, and dedicated carry logic for arithmetic functions. It supports SelectIO technology enabling mixed-voltage I/O banks with independent VCCO per bank and programmable slew rate control.

Configuration is performed via Master Serial mode using external PROM or JTAG boundary-scan interface. The device includes internal global clock networks with eight low-skew clock buffers and supports Digital Clock Managers (DCMs) for phase shifting, duty cycle correction, and frequency synthesis.

Key Specifications

Pinout & Package

XC3S400-5FG320C is housed in a 320-pin Fine-Pitch Ball Grid Array (FBGA) package with 20×20 array, 1.0 mm ball pitch, and 27 mm × 27 mm body size. Thermal pad on underside requires solder paste stencil design per IPC-7351B.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar FPGA-based digital logic and signal processing applications.

Compared with XC3S400-5FG320C, XC3S500E-5FG320C offers higher gate count in identical packaging for drop-in scalability, while XC6SLX45-3CSG324C delivers architectural improvements including reduced dynamic power and hardened peripherals at the cost of board redesign.

Availability

XC3S400-5FG320C is available at Aetrix Electronics and suitable for industrial motion controllers, automated test equipment, and medical imaging subsystems requiring stable component supply across extended production lifecycles.

Supply support for XC3S400-5FG320C 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 FPGA family for cost-sensitive, high-volume embedded applications.

The Spartan-3 series was designed for mainstream digital logic replacement, ASIC prototyping, and interface bridging in industrial, automotive, and communications systems where performance-per-watt and I/O flexibility are critical.

FAQ

What is the maximum operating junction temperature for XC3S400-5FG320C?

The XC3S400-5FG320C has a maximum operating junction temperature of 85°C under specified thermal conditions. This rating assumes proper PCB thermal vias beneath the thermal pad and airflow ≥200 LFM. Exceeding this limit risks timing violations and configuration loss. Derating curves in DS099 specify safe ambient limits based on board copper area and enclosure type. The XC3S400-5FG320C must be operated within this thermal envelope for reliable long-term function.

Does XC3S400-5FG320C support JTAG boundary-scan for in-system programming?

Yes, XC3S400-5FG320C fully supports IEEE 1149.1 JTAG boundary-scan through dedicated TCK, TMS, TDI, and TDO pins. This enables in-system configuration, debugging, and interconnect testing without removing the device. The JTAG TAP controller is integrated into the silicon and does not require external firmware. Configuration via JTAG is supported by Xilinx iMPACT and Vivado tools. The XC3S400-5FG320C uses standard JTAG instruction set for IDCODE, BYPASS, SAMPLE/PRELOAD, and EXTEST operations.

What I/O standards are supported by XC3S400-5FG320C?

XC3S400-5FG320C supports LVCMOS18, LVCMOS25, LVCMOS33, LVTTL, PCI, and HSTL Class I across its 241 user I/O pins. Each of the eight I/O banks operates independently with selectable VCCO (1.2 V to 3.3 V). Differential signaling is not natively supported - LVDS requires external resistors and careful layout. The XC3S400-5FG320C does not include built-in differential I/O drivers or termination.

How many Digital Clock Managers (DCMs) are included in XC3S400-5FG320C?

The XC3S400-5FG320C contains four Digital Clock Managers (DCMs), each capable of frequency synthesis, phase shifting, and duty cycle correction. These DCMs accept input clocks up to 280 MHz and generate up to two output clocks per DCM. They operate without external feedback and maintain ±1% duty cycle accuracy over process, voltage, and temperature. The XC3S400-5FG320C uses these DCMs to eliminate external clock ICs in timing-critical applications.

Is XC3S400-5FG320C RoHS compliant and lead-free?

Yes, XC3S400-5FG320C is RoHS compliant and manufactured with lead-free (Pb-free) ball metallurgy (SnAgCu) per JEDEC J-STD-020. The device meets EU Directive 2011/65/EU and carries the "RoHS Compliant" marking on the top-side laser etch. Moisture sensitivity level is MSL3 per J-STD-020, requiring bake before reflow if exposed beyond floor life. The XC3S400-5FG320C qualifies for lead-free reflow profiles with peak temperature ≤260°C.