The XC3S1000-4FG320C is a high-performance, cost-optimized Xilinx FPGA from the Spartan-3 family, manufactured by AMD (formerly Xilinx). Designed for applications requiring abundant logic resources and flexible I/O, this device delivers 1,000,000 system gates in a compact 320-ball Fine-pitch Ball Grid Array (FBGA) package. Whether you are designing communications hardware, consumer electronics, or industrial control systems, the XC3S1000-4FG320C offers a proven, production-ready solution.
What Is the XC3S1000-4FG320C?
The XC3S1000-4FG320C belongs to Xilinx’s Spartan-3 FPGA series — one of the most widely deployed FPGA families in embedded and digital design history. The part number breaks down as follows:
| Code Segment |
Meaning |
| XC3S |
Spartan-3 Family |
| 1000 |
1,000,000 System Gates |
| -4 |
Speed Grade (-4 = slowest/most cost-effective) |
| FG320 |
Fine-pitch BGA, 320-ball package |
| C |
Commercial temperature range (0°C to +85°C) |
XC3S1000-4FG320C Key Specifications
Core Logic Resources
| Parameter |
Value |
| System Gates |
1,000,000 |
| Logic Cells |
17,280 |
| CLB Slices |
7,680 |
| CLB Flip-Flops |
15,360 |
| Distributed RAM (bits) |
120,000 |
| Block RAM (bits) |
432,000 |
| Block RAM Blocks |
24 × 18Kb |
| Multipliers (18×18-bit) |
24 |
| DCMs (Digital Clock Managers) |
4 |
I/O and Packaging
| Parameter |
Value |
| Package Type |
FBGA (Fine-pitch Ball Grid Array) |
| Package Code |
FG320 |
| Total Ball Count |
320 |
| Maximum User I/O Pins |
221 |
| I/O Standards Supported |
LVTTL, LVCMOS, SSTL, HSTL, LVDS, and more |
| Differential I/O Pairs |
22 |
Electrical and Timing
| Parameter |
Value |
| Speed Grade |
-4 |
| Core Voltage (VCCINT) |
1.2V |
| I/O Voltage (VCCO) |
1.2V – 3.3V (bank selectable) |
| Temperature Range |
0°C to +85°C (Commercial) |
XC3S1000-4FG320C Package Information
The FG320 package is a 320-ball Fine-pitch Ball Grid Array with a 1.0mm ball pitch, measuring 19mm × 19mm. This compact footprint makes the XC3S1000-4FG320C well suited for space-constrained PCB designs while still offering 221 user-accessible I/O pins.
| Package Attribute |
Detail |
| Package Family |
FBGA |
| Ball Count |
320 |
| Ball Pitch |
1.0mm |
| Body Size |
19mm × 19mm |
| Moisture Sensitivity Level (MSL) |
MSL 3 / 168 Hours |
| RoHS Compliant |
Yes |
Spartan-3 Architecture Overview
CLB (Configurable Logic Block) Structure
Each CLB in the Spartan-3 architecture contains four slices. Every slice includes two 4-input look-up tables (LUTs), two flip-flops, and dedicated carry logic. This structure enables efficient implementation of counters, state machines, arithmetic units, and complex combinational logic.
Block RAM
The XC3S1000-4FG320C features 24 block RAM modules, each offering 18Kb of true dual-port memory. Block RAMs are ideal for implementing FIFOs, line buffers, lookup tables, and packet buffers in communications designs.
Digital Clock Manager (DCM)
Four DCMs provide on-chip clock synthesis, deskewing, phase shifting, and frequency division/multiplication. DCMs eliminate the need for external PLLs in many designs, reducing BOM cost and simplifying clock tree management.
Dedicated Multipliers
Twenty-four 18×18-bit hardware multipliers accelerate DSP operations such as FIR filters, FFTs, and PID controllers without consuming CLB resources.
Supported I/O Standards
The XC3S1000-4FG320C supports a broad range of single-ended and differential I/O standards, enabling interfacing with a wide variety of external components and buses.
| Standard Type |
Supported Standards |
| Single-Ended |
LVTTL, LVCMOS3.3 / 2.5 / 1.8 / 1.5 |
| High-Speed |
SSTL2 Class I/II, SSTL18 Class I/II, HSTL Class I |
| Differential |
LVDS, LVPECL, BLVDS, DIFF_SSTL2, DIFF_SSTL18 |
| PCI |
PCI 3.3V (33/66 MHz) |
Typical Applications for the XC3S1000-4FG320C
The XC3S1000-4FG320C is a versatile device used across many industries and design domains.
Communications and Networking
- Packet processing and protocol bridging
- Ethernet MAC implementation
- Serial-to-parallel conversion
- Custom framing engines
Industrial and Embedded Control
- Motor control with PWM generation
- Real-time sensor data aggregation
- Fieldbus protocol interfaces (CAN, SPI, I²C)
- Safety-critical state machine logic
Consumer Electronics
- Video signal processing (line buffering, scaling)
- Audio DSP pipelines
- Display controller logic
Test and Measurement
- High-speed data capture and logging
- Signal generation and pattern testing
- Reconfigurable instrument front-ends
Education and Prototyping
- Digital design coursework and lab exercises
- FPGA-based co-processor experiments
- Algorithm acceleration prototyping
XC3S1000-4FG320C vs. Similar Spartan-3 Devices
| Part Number |
System Gates |
User I/O |
Block RAM (bits) |
Package |
| XC3S250E-4FT256C |
250,000 |
172 |
216,000 |
FTBGA-256 |
| XC3S500E-4FT256C |
500,000 |
232 |
360,000 |
FTBGA-256 |
| XC3S1000-4FG320C |
1,000,000 |
221 |
432,000 |
FBGA-320 |
| XC3S1500-4FG320C |
1,500,000 |
221 |
576,000 |
FBGA-320 |
| XC3S2000-4FG456C |
2,000,000 |
270 |
720,000 |
FBGA-456 |
Ordering and Part Number Information
| Attribute |
Detail |
| Manufacturer |
AMD (Xilinx) |
| Part Number |
XC3S1000-4FG320C |
| Product Family |
Spartan-3 |
| Status |
Active / In Production |
| Temperature Grade |
Commercial (0°C to +85°C) |
| Packaging Options |
Tray |
| DigiKey Part Number |
122-1448-ND |
| ECCN / Export Classification |
EAR99 |
Design Tools and Support
Xilinx Spartan-3 devices are fully supported by the Xilinx ISE Design Suite (legacy tool). Designs are typically created in VHDL or Verilog, synthesized with XST, placed-and-routed with ISE, and programmed via JTAG using iMPACT or a compatible programmer.
For new designs, AMD recommends evaluating migration paths to Artix-7 or Kintex-7 devices, which offer significant performance and power improvements while maintaining ISE/Vivado tool compatibility.
| Tool |
Purpose |
| Xilinx ISE Design Suite |
Synthesis, P&R, Timing Analysis |
| ISIM / ModelSim |
HDL Simulation |
| iMPACT |
JTAG Programming |
| ChipScope Pro |
On-chip Logic Analyzer |
| CORE Generator |
IP Core Generation |
Frequently Asked Questions (FAQ)
Q: What is the difference between XC3S1000-4FG320C and XC3S1000-5FG320C?
A: The only difference is the speed grade. The “-5” device is faster (lower propagation delay), while the “-4” is the most cost-effective speed grade in the family.
Q: Is the XC3S1000-4FG320C RoHS compliant?
A: Yes, the “C” suffix in the part number denotes commercial temperature range, and AMD Xilinx Spartan-3 devices in the FG320 package are available in RoHS-compliant lead-free versions.
Q: Can I program the XC3S1000-4FG320C using SPI Flash?
A: Yes. The Spartan-3 supports Master SPI, Master Serial, JTAG, and Slave SelectMAP configuration modes. An external SPI Flash (e.g., M25P series) is commonly used for standalone operation.
Q: What software do I need to develop for the XC3S1000-4FG320C?
A: You will need Xilinx ISE Design Suite (version 14.7 is the final release supporting Spartan-3). It is available as a free WebPACK edition for smaller designs.
Summary
The XC3S1000-4FG320C is a mature, reliable, and cost-effective FPGA offering 1 million system gates, 221 user I/O pins, 24 block RAMs, and 4 DCMs in a compact 320-ball BGA package. Its proven Spartan-3 architecture, broad I/O standard support, and robust ecosystem of development tools make it an excellent choice for production designs in communications, industrial, consumer, and embedded markets. Engineers seeking a dependable mid-range FPGA for their next board bring-up will find the XC3S1000-4FG320C a well-supported and readily available solution.
