AMD XC3S400A-4FGG400C

Overview

XC3S400A-4FGG400C from AMD (formerly Xilinx) is a Spartan-3A FPGA with 400,000 system gates, 8,064 logic cells, and 216 I/O pins in a 400-pin Fine-Pitch Ball Grid Array (FBGA) package. It operates at -4 speed grade (tPD = 4.5 ns), supports SelectIO™ standards up to 622 Mbps, and targets cost-sensitive industrial control and communication interface applications.

For engineers reviewing the XC3S400A-4FGG400C datasheet, pinout, applications, or equivalent options, key selection criteria include I/O voltage flexibility (1.2 V to 3.3 V), embedded block RAM capacity (288 kbits), and support for DDR/DDR2 SDRAM interfaces in resource-constrained designs.

Technical Context

The XC3S400A-4FGG400C implements a hierarchical FPGA architecture with configurable logic blocks (CLBs), distributed RAM, and dedicated carry logic. It integrates twelve 18×18 multipliers and supports digital clock managers (DCMs) for internal clock synthesis and phase alignment.

It uses 90 nm CMOS process technology, features JTAG boundary-scan compliance (IEEE 1149.1), and supports configuration via Master Serial, Slave Serial, or Boundary Scan modes using external PROM or processor-controlled loading.

Key Specifications

Pinout & Package

XC3S400A-4FGG400C is housed in a 400-pin Fine-Pitch Ball Grid Array (FBGA) package with 216 user I/Os, 8 dedicated configuration pins, and power/ground balls arranged per Xilinx SPARTAN-3A PCB layout guidelines.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar FPGA-based interface and control applications.

Compared with XC3S400A-4FGG400C, XC3S500A-4FGG400C offers immediate scalability within identical footprint and toolchain, while XC6SLX45-3CSG324C delivers architectural upgrades at the cost of layout change and migration effort.

Availability

XC3S400A-4FGG400C is available at Aetrix Electronics and suitable for industrial automation, telecom line card development, and legacy system modernization requiring stable component supply and long-term obsolescence management.

Supply support for XC3S400A-4FGG400C 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 maintains the Spartan family as part of its adaptive computing portfolio for cost-optimized, low-power programmable logic solutions.

The Spartan-3A product line was designed specifically for high-volume, price-sensitive applications requiring reliable I/O interfacing, moderate logic density, and seamless integration with legacy and mixed-voltage systems.

FAQ

What is the maximum supported I/O standard voltage for XC3S400A-4FGG400C?

XC3S400A-4FGG400C supports I/O standards ranging from 1.2 V to 3.3 V across independent banks. Each bank can be configured for a specific VCCO voltage, enabling simultaneous interfacing with multiple voltage domains such as 1.8 V sensors and 3.3 V microcontrollers - a capability confirmed in Xilinx DS312 v2.5 specification.

Does XC3S400A-4FGG400C include built-in configuration memory?

No, XC3S400A-4FGG400C does not include non-volatile configuration memory. It relies on external serial PROM (e.g., XCF02S), microcontroller loading, or JTAG for bitstream initialization. Configuration SRAM is volatile and must be reloaded at power-up, as documented in the Spartan-3A Configuration User Guide (UG332).

Can XC3S400A-4FGG400C implement a DDR SDRAM controller?

Yes, XC3S400A-4FGG400C can implement a functional DDR SDRAM controller using its DCMs for clock generation and phase alignment, along with its 216 I/Os and block RAM for command/address/data paths. Reference designs such as XAPP778 demonstrate working DDR1 controllers achieving 200 MHz operation.

What thermal package rating applies to XC3S400A-4FGG400C?

XC3S400A-4FGG400C carries the 'C' temperature grade, specifying commercial operation from 0 °C to +70 °C ambient. This rating is defined in the device marking and confirmed in DS312 Table 1, and applies to the FGG400 package variant under natural convection conditions.

Is JTAG boundary-scan supported on XC3S400A-4FGG400C?

Yes, XC3S400A-4FGG400C fully supports IEEE 1149.1 JTAG boundary-scan through dedicated TCK, TMS, TDI, and TDO pins. This enables in-circuit testing, programming, and debug visibility - verified in UG332 Section 3 and implemented in Xilinx iMPACT and Vivado tools.