11

Spartan-6 Family Overview

DS160 (v2.0) October 25, 2011 Product Specification

General Description
The Spartan®-6 family provides leading system integration capabilities with the lowest total cost for high-volume applications. The
thirteen-member family delivers expanded densities ranging from 3,840 to 147,443 logic cells, with half the power consumption of previous
Spartan families, and faster, more comprehensive connectivity. Built on a mature 45 nm low-power copper process technology that
delivers the optimal balance of cost, power, and performance, the Spartan-6 family offers a new, more efficient, dual-register 6-input look-
up table (LUT) logic and a rich selection of built-in system-level blocks. These include 18 Kb (2 x 9 Kb) block RAMs, second generation
DSP48A1 slices, SDRAM memory controllers, enhanced mixed-mode clock management blocks, SelectIO™ technology, power-
optimized high-speed serial transceiver blocks, PCI Express® compatible Endpoint blocks, advanced system-level power management
modes, auto-detect configuration options, and enhanced IP security with AES and Device DNA protection. These features provide a low-
cost programmable alternative to custom ASIC products with unprecedented ease of use. Spartan-6 FPGAs offer the best solution for
high-volume logic designs, consumer-oriented DSP designs, and cost-sensitive embedded applications. Spartan-6 FPGAs are the
programmable silicon foundation for Targeted Design Platforms that deliver integrated software and hardware components that enable
designers to focus on innovation as soon as their development cycle begins.
Summary of Spartan-6 FPGA Features
• Spartan-6 Family: • Integrated Memory Controller blocks
• Spartan-6 LX FPGA: Logic optimized • DDR, DDR2, DDR3, and LPDDR support
• Spartan-6 LXT FPGA: High-speed serial connectivity • Data rates up to 800 Mb/s (12.8 Gb/s peak bandwidth)
• Designed for low cost • Multi-port bus structure with independent FIFO to reduce
• Multiple efficient integrated blocks design timing issues
• Optimized selection of I/O standards • Abundant logic resources with increased logic capacity
• Staggered pads • Optional shift register or distributed RAM support
• High-volume plastic wire-bonded packages • Efficient 6-input LUTs improve performance and
• Low static and dynamic power minimize power
• 45 nm process optimized for cost and low power • LUT with dual flip-flops for pipeline centric applications
• Hibernate power-down mode for zero power • Block RAM with a wide range of granularity
• Suspend mode maintains state and configuration with • Fast block RAM with byte write enable
multi-pin wake-up, control enhancement • 18 Kb blocks that can be optionally programmed as two
• Lower-power 1.0V core voltage (LX FPGAs, -1L only) independent 9 Kb block RAMs
• High performance 1.2V core voltage (LX and LXT • Clock Management Tile (CMT) for enhanced performance
FPGAs, -2, -3, and -3N speed grades) • Low noise, flexible clocking
• Multi-voltage, multi-standard SelectIO™ interface banks • Digital Clock Managers (DCMs) eliminate clock skew
• Up to 1,080 Mb/s data transfer rate per differential I/O and duty cycle distortion
• Selectable output drive, up to 24 mA per pin • Phase-Locked Loops (PLLs) for low-jitter clocking
• 3.3V to 1.2V I/O standards and protocols • Frequency synthesis with simultaneous multiplication,
• Low-cost HSTL and SSTL memory interfaces division, and phase shifting
• Hot swap compliance • Sixteen low-skew global clock networks
• Adjustable I/O slew rates to improve signal integrity • Simplified configuration, supports low-cost standards
• High-speed GTP serial transceivers in the LXT FPGAs • 2-pin auto-detect configuration
• Up to 3.2 Gb/s • Broad third-party SPI (up to x4) and NOR flash support
• High-speed interfaces including: Serial ATA, Aurora, • Feature rich Xilinx Platform Flash with JTAG
1G Ethernet, PCI Express, OBSAI, CPRI, EPON, • MultiBoot support for remote upgrade with multiple
GPON, DisplayPort, and XAUI bitstreams, using watchdog protection
• Integrated Endpoint block for PCI Express designs (LXT) • Enhanced security for design protection
• Low-cost PCI® technology support compatible with the • Unique Device DNA identifier for design authentication
33 MHz, 32- and 64-bit specification. • AES bitstream encryption in the larger devices
• Efficient DSP48A1 slices • Faster embedded processing with enhanced, low cost,
• High-performance arithmetic and signal processing MicroBlaze™ soft processor
• Fast 18 x 18 multiplier and 48-bit accumulator • Industry-leading IP and reference designs
• Pipelining and cascading capability
• Pre-adder to assist filter applications

© 2009–2011 Xilinx, Inc. Xilinx, the Xilinx logo, Artix, ISE, Kintex, Spartan, Virtex, Zynq, and other designated brands included herein are trademarks of Xilinx in the United States
and other countries. PCI, PCIe and PCI Express are trademarks of PCI-SIG and used under license. All other trademarks are the property of their respective owners.

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Product Specification 1
 Spartan-6 Family Overview

Spartan-6 FPGA Feature Summary

Table 1: Spartan-6 FPGA Feature Summary by Device
Configurable Logic Blocks (CLBs) Block RAM Blocks
Memory
Endpoint Maximum Total Max
Logic DSP48A1
CMTs(5)
Controller
Device Max Blocks for GTP I/O User
Cells(1) Slices(3) Blocks
Slices(2) Flip-Flops Distributed 18 Kb(4) Max (Kb) PCI Express Transceivers Banks I/O
(Max)(6)
RAM (Kb)

XC6SLX4 3,840 600 4,800 75 8 12 216 2 0 0 0 4 132

XC6SLX9 9,152 1,430 11,440 90 16 32 576 2 2 0 0 4 200
XC6SLX16 14,579 2,278 18,224 136 32 32 576 2 2 0 0 4 232
XC6SLX25 24,051 3,758 30,064 229 38 52 936 2 2 0 0 4 266
XC6SLX45 43,661 6,822 54,576 401 58 116 2,088 4 2 0 0 4 358
XC6SLX75 74,637 11,662 93,296 692 132 172 3,096 6 4 0 0 6 408
XC6SLX100 101,261 15,822 126,576 976 180 268 4,824 6 4 0 0 6 480
XC6SLX150 147,443 23,038 184,304 1,355 180 268 4,824 6 4 0 0 6 576
XC6SLX25T 24,051 3,758 30,064 229 38 52 936 2 2 1 2 4 250
XC6SLX45T 43,661 6,822 54,576 401 58 116 2,088 4 2 1 4 4 296
XC6SLX75T 74,637 11,662 93,296 692 132 172 3,096 6 4 1 8 6 348
XC6SLX100T 101,261 15,822 126,576 976 180 268 4,824 6 4 1 8 6 498
XC6SLX150T 147,443 23,038 184,304 1,355 180 268 4,824 6 4 1 8 6 540

Notes:
1. Spartan-6 FPGA logic cell ratings reflect the increased logic cell capability offered by the new 6-input LUT architecture.
2. Each Spartan-6 FPGA slice contains four LUTs and eight flip-flops.
3. Each DSP48A1 slice contains an 18 x 18 multiplier, an adder, and an accumulator.
4. Block RAMs are fundamentally 18 Kb in size. Each block can also be used as two independent 9 Kb blocks.
5. Each CMT contains two DCMs and one PLL.
6. Memory Controller Blocks are not supported in the -3N speed grade.

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 Spartan-6 Family Overview

Spartan-6 FPGA Device-Package Combinations and Available I/Os

Spartan-6 FPGA package combinations with the available I/Os and GTP transceivers per package are shown in Table 2.
Due to the transceivers, the LX and LXT pinouts are not compatible.

Table 2: Spartan-6 Device-Package Combinations and Maximum Available I/Os

Package CPG196(1) TQG144(1) CSG225(2) FT(G)256(3) CSG324 FG(G)484(3,4) CSG484(4) FG(G)676(3) FG(G)900(3)
Body Size 8x8 20 x 20 13 x 13 17 x 17 15 x 15 23 x 23 19 x 19 27 x 27 31 x 31
(mm)
Pitch (mm) 0.5 0.5 0.8 1.0 0.8 1.0 0.8 1.0 1.0
User User User User User
Device User I/O User I/O User I/O User I/O GTPs
I/O
GTPs
I/O
GTPs
I/O
GTPs
I/O
GTPs
I/O
XC6SLX4 106 102 132
XC6SLX9 106 102 160 186 NA 200
XC6SLX16 106 160 186 NA 232
XC6SLX25 186 NA 226 NA 266
XC6SLX45 NA 218 NA 316 NA 320 NA 358
XC6SLX75 NA 280 NA 328 NA 408
XC6SLX100 NA 326 NA 338 NA 480
XC6SLX150 NA 338 NA 338 NA 498 NA 576
XC6SLX25T 2 190 2 250
XC6SLX45T 4 190 4 296 4 296
XC6SLX75T 4 268 4 292 8 348
XC6SLX100T 4 296 4 296 8 376 8 498
XC6SLX150T 4 296 4 296 8 396 8 540

Notes:
1. There is no memory controller on the devices in these packages.
2. Memory controller block support is x8 on the XC6SLX9 and XC6SLX16 devices in the CSG225 package. There is no memory controller in the
XC6SLX4.
3. These devices are available in both Pb and Pb-free (additional G) packages as standard ordering options.
4. These packages support two of the four memory controllers in the XC6SLX75, XC6SLX75T, XC6SLX100, XC6SLX100T, XC6SLX150, and
XC6SLX150T devices.

Configuration
Spartan-6 FPGAs store the customized configuration data in SRAM-type internal latches. The number of configuration bits
is between 3 Mb and 33 Mb depending on device size and user-design implementation options. The configuration storage
is volatile and must be reloaded whenever the FPGA is powered up. This storage can also be reloaded at any time by pulling
the PROGRAM_B pin Low. Several methods and data formats for loading configuration are available.
Bit-serial configurations can be either master serial mode, where the FPGA generates the configuration clock (CCLK) signal,
or slave serial mode, where the external configuration data source also clocks the FPGA. For byte-wide configurations,
master SelectMAP mode generates the CCLK signal while slave SelectMAP mode receives the CCLK signal for the 8- and
16-bit-wide transfer. In master serial mode, the beginning of the bitstream can optionally switch the clocking source to an
external clock, which can be faster or more precise than the internal clock. The available JTAG pins use boundary-scan
protocols to load bit-serial configuration data.

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The bitstream configuration information is generated by the ISE® software using a program called BitGen. The configuration
process typically executes the following sequence:
• Detects power-up (power-on reset) or PROGRAM_B when Low.
• Clears the whole configuration memory.
• Samples the mode pins to determine the configuration mode: master or slave, bit-serial or parallel.
• Loads the configuration data starting with the bus-width detection pattern followed by a synchronization word, checks
for the proper device code, and ends with a cyclic redundancy check (CRC) of the complete bitstream.
• Starts a user-defined sequence of events: releasing the internal reset (or preset) of flip-flops, optionally waiting for the
DCMs and/or PLLs to lock, activating the output drivers, and transitioning the DONE pin to High.
The Master Serial Peripheral Interface (SPI) and the Master Byte-wide Peripheral Interface (BPI) are two common methods
used for configuring the FPGA. The Spartan-6 FPGA configures itself from a directly attached industry-standard SPI serial
flash PROM. The Spartan-6 FPGA can configure itself via BPI when connected to an industry-standard parallel NOR flash.
Note that BPI configuration is not supported in the XC6SLX4, XC6SLX25, and XC6SLX25T nor is BPI available when using
Spartan-6 FPGAs in TQG144 and CPG196 packages.
Spartan-6 FPGAs support MultiBoot configuration, where two or more FPGA configuration bitstreams can be stored in a
single configuration source. The FPGA application controls which configuration to load next and when to load it.
Spartan-6 FPGAs also include a unique, factory-programmed Device DNA identifier that is useful for tracking purposes, anti-
cloning designs, or IP protection. In the largest devices, bitstreams can be copy protected using AES encryption.

Readback
Most configuration data can be read back without affecting the system’s operation.

CLBs, Slices, and LUTs

Each configurable logic block (CLB) in Spartan-6 FPGAs consists of two slices, arranged side-by-side as part of two vertical
columns. There are three types of CLB slices in the Spartan-6 architecture: SLICEM, SLICEL, and SLICEX. Each slice
contains four LUTs, eight flip-flops, and miscellaneous logic. The LUTs are for general-purpose combinatorial and
sequential logic support. Synthesis tools take advantage of these highly efficient logic, arithmetic, and memory features.
Expert designers can also instantiate them.

SLICEM
One quarter (25%) of Spartan-6 FPGA slices are SLICEMs. Each of the four SLICEM LUTs can be configured as either a
6-input LUT with one output, or as dual 5-input LUTs with identical 5-bit addresses and two independent outputs. These
LUTs can also be used as distributed 64-bit RAM with 64 bits or two times 32 bits per LUT, as a single 32-bit shift register
(SRL32), or as two 16-bit shift registers (SRL16s) with addressable length. Each LUT output can be registered in a flip-flop
within the CLB. For arithmetic operations, a high-speed carry chain propagates carry signals upwards in a column of slices.

SLICEL
One quarter (25%) of Spartan-6 FPGA slices are SLICELs, which contain all the features of the SLICEM except the
memory/shift register function.

SLICEX
One half (50%) of Spartan-6 FPGA slices are SLICEXs. The SLICEXs have the same structure as SLICELs except the
arithmetic carry option and the wide multiplexers.

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Clock Management
Each Spartan-6 FPGA has up to six CMTs, each consisting of two DCMs and one PLL, which can be used individually or
cascaded.

DCM
The DCM provides four phases of the input frequency (CLKIN): shifted 0°, 90°, 180°, and 270° (CLK0, CLK90, CLK180, and
CLK270). It also provides a doubled frequency CLK2X and its complement CLK2X180. The CLKDV output provides a
fractional clock frequency that can be phase-aligned to CLK0. The fraction is programmable as every integer from 2 to 16,
as well as 1.5, 2.5, 3.5 . . . 7.5. CLKIN can optionally be divided by 2. The DCM can be a zero-delay clock buffer when a clock
signal drives CLKIN, while the CLK0 output is fed back to the CLKFB input.

Frequency Synthesis
Independent of the basic DCM functionality, the frequency synthesis outputs CLKFX and CLKFX180 can be programmed to
generate any output frequency that is the DCM input frequency (FIN) multiplied by M and simultaneously divided by D, where
M can be any integer from 2 to 32 and D can be any integer from 1 to 32.

Phase Shifting
With CLK0 connected to CLKFB, all nine CLK outputs (CLK0, CLK90, CLK180, CLK270, CLK2X, CLK2X180, CLKDV,
CLKFX, and CLKFX180) can be shifted by a common amount, defined as any integer multiple of a fixed delay. A fixed DCM
delay value (fraction of the input period) can be established by configuration and can also be incremented or decremented
dynamically.

Spread-Spectrum Clocking
The DCM can accept and track typical spread-spectrum clock inputs, provided they abide by the input clock specifications
listed in the Spartan-6 FPGA Data Sheet: DC and Switching Characteristics. Spartan-6 FPGAs can generate a spread-
spectrum clock source from a standard fixed-frequency oscillator.

PLL
The PLL can serve as a frequency synthesizer for a wider range of frequencies and as a jitter filter for incoming clocks in
conjunction with the DCMs. The heart of the PLL is a voltage-controlled oscillator (VCO) with a frequency range of
400 MHz to 1,080 MHz, thus spanning more than one octave. Three sets of programmable frequency dividers (D, M, and O)
adapt the VCO to the required application.
The pre-divider D (programmable by configuration) reduces the input frequency and feeds one input of the traditional PLL
phase comparator. The feedback divider (programmable by configuration) acts as a multiplier because it divides the VCO
output frequency before feeding the other input of the phase comparator. D and M must be chosen appropriately to keep the
VCO within its controllable frequency range.
The VCO has eight equally spaced outputs (0°, 45°, 90°, 135°, 180°, 225°, 270°, and 315°). Each can be selected to drive
one of the six output dividers, O0 to O5 (each programmable by configuration to divide by any integer from 1 to 128).

Clock Distribution
Each Spartan-6 FPGA provides abundant clock lines to address the different clocking requirements of high fanout, short
propagation delay, and extremely low skew.

Global Clock Lines

In each Spartan-6 FPGA, 16 global-clock lines have the highest fanout and can reach every flip-flop clock. Global clock lines
must be driven by global clock buffers, which can also perform glitchless clock multiplexing and the clock enable function.
Global clocks are often driven from the CMTs, which can completely eliminate the basic clock distribution delay.

I/O Clocks
I/O clocks are especially fast and serve only the localized input and output delay circuits and the I/O serializer/deserializer
(SERDES) circuits, as described in the I/O Logic section.

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Block RAM
Every Spartan-6 FPGA has between 12 and 268 dual-port block RAMs, each storing 18 Kb. Each block RAM has two
completely independent ports that share only the stored data.

Synchronous Operation
Each memory access, whether read or write, is controlled by the clock. All inputs, data, address, clock enables, and write
enables are registered. The data output is always latched, retaining data until the next operation. An optional output data
pipeline register allows higher clock rates at the cost of an extra cycle of latency.
During a write operation in dual-port mode, the data output can reflect either the previously stored data, the newly written
data, or remain unchanged.

Programmable Data Width

• Each port can be configured as 16K × 1, 8K × 2, 4K × 4, 2K × 9 (or 8), 1K × 18 (or 16), or 512 x 36 (or 32).
• The x9, x18, and x36 configurations include parity bits. The two ports can have different aspect ratios.
• Each block RAM can be divided into two completely independent 9 Kb block RAMs that can each be configured to any
aspect ratio from 8K x 1 to 512 x 18, with 256 x 36 supported in simple dual-port mode.

Memory Controller Block

Most Spartan-6 devices include dedicated memory controller blocks (MCBs), each targeting a single-chip DRAM (either
DDR, DDR2, DDR3, or LPDDR), and supporting access rates of up to 800 Mb/s.
The MCB has dedicated routing to predefined FPGA I/Os. If the MCB is not used, these I/Os are available as general
purpose FPGA I/Os. The memory controller offers a complete multi-port arbitrated interface to the logic inside the
Spartan-6 FPGA. Commands can be pushed, and data can be pushed to and pulled from independent built-in FIFOs, using
conventional FIFO control signals. The multi-port memory controller can be configured in many ways. An internal 32-, 64-,
or 128-bit data interface provides a simple and reliable interface to the MCB.
The MCB can be connected to 4-, 8-, or 16-bit external DRAM. The MCB, in many applications, provides a faster DRAM
interface compared to traditional internal data buses, which are wider and are clocked at a lower frequency. The FPGA logic
interface can be flexibly configured irrespective of the physical memory device. The MCB functionality is not supported in the
-3N speed grade.

Digital Signal Processing—DSP48A1 Slice

DSP applications use many binary multipliers and accumulators, best implemented in dedicated DSP slices. All
Spartan-6 FPGAs have many dedicated, full-custom, low-power DSP slices, combining high speed with small size, while
retaining system design flexibility.
Each DSP48A1 slice consists of a dedicated 18 × 18 bit two's complement multiplier and a 48-bit accumulator, both capable
of operating at up to 390 MHz. The DSP48A1 slice provides extensive pipelining and extension capabilities that enhance
speed and efficiency of many applications, even beyond digital signal processing, such as wide dynamic bus shifters,
memory address generators, wide bus multiplexers, and memory-mapped I/O register files. The accumulator can also be
used as a synchronous up/down counter. The multiplier can perform barrel shifting.

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Input/Output
The number of I/O pins varies from 102 to 576, depending on device and package size. Each I/O pin is configurable and can
comply with a large number of standards, using up to 3.3V. The Spartan-6 FPGA SelectIO Resources User Guide describes
the I/O compatibilities of the various I/O options. With the exception of supply pins and a few dedicated configuration pins,
all other package pins have the same I/O capabilities, constrained only by certain banking rules. All user I/O is bidirectional;
there are no input-only pins.
All I/O pins are organized in banks, with four banks on the smaller devices and six banks on the larger devices. Each bank
has several common VCCO output supply-voltage pins, which also powers certain input buffers. Some single-ended input
buffers require an externally applied reference voltage (VREF). There are several dual-purpose VREF-I/O pins in each bank.
In a given bank, when I/O standard calls for a VREF voltage, each VREF pin in that bank must be connected to the same
voltage rail and can not be used as an I/O pin.

I/O Electrical Characteristics

Single-ended outputs use a conventional CMOS push/pull output structure, driving High towards VCCO or Low towards
ground, and can be put into high-Z state. Many I/O features are available to the system designer to optionally invoke in each
I/O in their design, such as weak internal pull-up and pull-down resistors, strong internal split-termination input resistors,
adjustable output drive-strengths and slew-rates, and differential termination resistors. See the Spartan-6 FPGA SelectIO
Resources User Guide for more details on available options for each I/O standard.

I/O Logic
Input and Output Delay
This section describes the available logic resources connected to the I/O interfaces. All inputs and outputs can be configured
as either combinatorial or registered. Double data rate (DDR) is supported by all inputs and outputs. Any input or output can
be individually delayed by up to 256 increments (except in the -1L speed grade). This is implemented as IODELAY2. The
identical delay value is available either for data input or output. For a bidirectional data line, the transfer from input to output
delay is automatic. The number of delay steps can be set by configuration and can also be incremented or decremented
while in use.
Because these tap delays vary with supply voltage, process, and temperature, an optional calibration mechanism is built into
each IODELAY2:
• For source synchronous designs where more accuracy is required, the calibration mechanism can (optionally)
determine dynamically how many taps are needed to delay data by one full I/O clock cycle, and then programs the
IODELAY2 with 50% of that value, thus centering the I/O clock in the middle of the data eye.
• A special mode is available only for differential inputs, which uses a phase-detector mechanism to determine whether
the incoming data signal is being accurately sampled in the middle of the eye. The results from the phase-detector logic
can be used to either increment or decrement the input delay, one tap at a time, to ensure error-free operation at very
high bit rates.

ISERDES and OSERDES

Many applications combine high-speed bit-serial I/O with slower parallel operation inside the device. This requires a
serializer and deserializer (SerDes) inside the I/O structure. Each input has access to its own deserializer (serial-to-parallel
converter) with programmable parallel width of 2, 3, or 4 bits. Where differential inputs are used, the two serializers can be
cascaded to provide parallel widths of 5, 6, 7, or 8 bits. Each output has access to its own serializer (parallel-to-serial
converter) with programmable parallel width of 2, 3, or 4 bits. Two serializers can be cascaded when a differential driver is
used to give access to bus widths of 5, 6, 7, or 8 bits.
When distributing a double data rate clock, all SerDes data is actually clocked in/out at single data rate to eliminate the
possibility of bit errors due to duty cycle distortion. This faster single data rate clock is either derived via frequency
multiplication in a PLL, or doubled locally in each IOB by differentiating both clock edges when the incoming clock uses
double data rate.

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Low-Power Gigabit Transceiver

Ultra-fast data transmission between ICs, over the backplane, or over longer distances is becoming increasingly popular and
important. It requires specialized dedicated on-chip circuitry and differential I/O capable of coping with the signal integrity
issues at these high data rates.
All Spartan-6 LXT devices have 2–8 gigabit transceiver circuits. Each GTP transceiver is a combined transmitter and
receiver capable of operating at data rates up to 3.2 Gb/s. The transmitter and receiver are independent circuits that use
separate PLLs to multiply the reference frequency input by certain programmable numbers between 2 and 25, to become
the bit-serial data clock. Each GTP transceiver has a large number of user-definable features and parameters. All of these
can be defined during device configuration, and many can also be modified during operation.

Transmitter
The transmitter is fundamentally a parallel-to-serial converter with a conversion ratio of 8, 10, 16, or 20. The transmitter
output drives the PC board with a single-channel differential current-mode logic (CML) output signal.
TXOUTCLK is the appropriately divided serial data clock and can be used directly to register the parallel data coming from
the internal logic. The incoming parallel data is fed through a small FIFO and can optionally be modified with the 8B/10B
algorithm to guarantee a sufficient number of transitions. The bit-serial output signal drives two package pins with
complementary CML signals. This output signal pair has programmable signal swing as well as programmable pre-
emphasis to compensate for PC board losses and other interconnect characteristics.

Receiver
The receiver is fundamentally a serial-to-parallel converter, changing the incoming bit serial differential signal into a parallel
stream of words, each 8, 10, 16, or 20 bits wide. The receiver takes the incoming differential data stream, feeds it through a
programmable equalizer (to compensate for the PC board and other interconnect characteristics), and uses the FREF input
to initiate clock recognition. There is no need for a separate clock line. The data pattern uses non-return-to-zero (NRZ)
encoding and optionally guarantees sufficient data transitions by using the 8B/10B encoding scheme. Parallel data is then
transferred into the FPGA logic using the RXUSRCLK clock. The serial-to-parallel conversion ratio can be 8, 10, 16, or 20.

Integrated Endpoint Block for PCI Express Designs

The PCI Express standard is a packet-based, point-to-point serial interface standard. The differential signal transmission
uses an embedded clock, which eliminates the clock-to-data skew problems of traditional wide parallel buses.
The PCI Express Base Specification 1.1 defines bit rate of 2.5 Gb/s per lane, per direction (transmit and receive). When
using 8B/10B encoding, this supports a data rate of 2.0 Gb/s per lane.
The Spartan-6 LXT devices include one integrated Endpoint block for PCI Express technology that is compliant with the PCI
Express Base Specification Revision 1.1. This block is highly configurable to system design requirements and operates as
a compliant single lane Endpoint. The integrated Endpoint block interfaces to the GTP transceivers for serialization/de-
serialization, and to block RAMs for data buffering. Combined, these elements implement the physical layer, data link layer,
and transaction layer of the protocol.
Xilinx provides a light-weight (<200 LUT), configurable, easy-to-use LogiCORE™ IP that ties the various building blocks (the
integrated Endpoint block for PCI Express technology, the GTP transceivers, block RAM, and clocking resources) into a
compliant Endpoint solution. The system designer has control over many configurable parameters: maximum payload size,
reference clock frequency, and base address register decoding and filtering.
More information and documentation on solutions for PCI Express designs can be found at:
http://www.xilinx.com/technology/protocols/pciexpress.htm

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Spartan-6 FPGA Ordering Information

Table 3 shows the speed and temperature grades available in the different Spartan-6 devices. Some devices might not be
available in every speed and temperature grade.
Table 3: Speed Grade and Temperature Ranges
Speed Grade and Temperature Range
Device Family Commercial (C) Industrial (I)
0°C to +85°C –40°C to +100°C
Spartan-6 LX -3, -3N, -2, -1L -3, -3N, -2, -1L
Spartan-6 LXT -3, -3N, -2 -3, -3N, -2

The Spartan-6 FPGA ordering information shown in Figure 1 applies to all packages, including Pb-Free. Refer to the
Package Marking section of UG385, Spartan-6 FPGA Packaging and Pinouts for a more detailed explanation of the device
markings.
X-Ref Target - Figure 1

Example: XC6SLX100T-2FGG676C

Device Type
Temperature Range:
Speed Grade C = Commercial (Tj = 0°C to +85°C)
(-L1(1), -2, -3, -N3(2))
I = Industrial (Tj = –40°C to +100°C)
Note:
1) -L1 is the ordering code for the lower power, -1L speed grade.
Number of Pins
Not all devices are offered in this version (LX only).
Pb-Free
See the Spartan-6 FPGA data sheet for more information.
2) -N3 is the ordering code for the -3N speed grade, Package Type
which indicates the devices in which MCB functionality is not supported. DS160_01_011311

Figure 1: Spartan-6 FPGA Ordering Information

Revision History
The following table shows the revision history for this document:

Date Version Description of Revisions

02/02/09 1.0 Initial Xilinx release.
05/05/09 1.1 Updated and simplified Designed for low cost, Multi-voltage, multi-standard SelectIO™ interface
banks, and Integrated Memory Controller blocks sections on page 1. Clarified PCI support on page 1is
only for the 33 MHz specification. Revised number of logic cells, slices, and maximum user I/O, and
added number of flip-flops to Table 1. In Table 2, revised user I/O counts, removed the XC6SLX25 in
the CSG225 package and the XC6SLX45T in the FGG676 package, added XC6SLX9 in the FT(G)256
package and XC6SLX45 in the CSG324 package, and added notes. Clerical edits to the following
sections: Dynamic Reconfiguration Port, Readback, CLBs, Slices, and LUTs, Frequency Synthesis,
PLL, Programmable Data Width, and Memory Controller Block. Clarified I/O pin range, VREF banks,
and electrical characteristics in the Input/Output section.
06/24/09 1.2 Updated device/package combinations in Table 1 and Table 2 including adding the XC6SLX75 and
XC6SLX75T devices. Added ordering information and FPGA documentation sections. Removed
partial reconfiguration discussion from the Readback section.
11/05/09 1.3 Updated Figure 1, page 9 to show -4 speed grade. Added 64-bit PCI support on page 1. Updated User
I/O numbers in Table 1and Table 2. Clarifying edits to these sections: Configuration, Digital Signal
Processing—DSP48A1 Slice, Input/Output, and PCI Express documentation.

DS160 (v2.0) October 25, 2011 www.xilinx.com

Product Specification 9
 Spartan-6 Family Overview

Date Version Description of Revisions

03/03/10 1.4 Updated the slice counts for the LX25 and LX25T in Table 1. Revised the Dynamic Reconfiguration
Port section. Added to the Spread-Spectrum Clocking section. Changed the PLL VCO maximum
frequency to 1080 MHz and the DSP48A1 slice maximum frequency to 320 MHz due to the addition
of the -4 speed specification. Clarified configurations in the Programmable Data Width section.
Updated Low-Power Gigabit Transceiver operating rate.
08/02/10 1.5 Updated data transfer rate per differential I/O from 1,050 Mb/s to 1,080 Mb/s in Summary of Spartan-6
FPGA Features. Added the -3N speed grade to appropriate section throughout the document,
including Figure 1. Updated category in Table 2 from Size to Body Size. Updated the Configuration
section with SPI and BPI interface information. Removed the Dynamic Reconfiguration Port section.
Updated the operating speed of the DSP48A1 slice multiplier and accumulator to 390 MHz in Digital
Signal Processing—DSP48A1 Slice. Updated Input and Output Delay.
11/05/10 1.6 In Summary of Spartan-6 FPGA Features and in Low-Power Gigabit Transceiver, updated GTP serial
transceiver data rate to 3.2 Gb/s. Updated the notes in Figure 1. Added DS170, XA Spartan-6
Automotive FPGA Family Overview to the Spartan-6 FPGA Documentation.
03/21/11 1.7 Updated from Advance to Preliminary Specification. Removed -4 speed grade from Summary of
Spartan-6 FPGA Features and Figure 1 per XCN11008. Updated Integrated Endpoint Block for PCI
Express Designs and Input and Output Delay.
10/25/11 2.0 Updated from Preliminary Specification to Production Specification. Updated Configuration, including
the range of configuration bits to 3 Mb and 33 Mb, and Input and Output Delay. Updated Spartan-6
FPGA Ordering Information and added Table 3. Added Defense-Grade Spartan-6Q Family Overview
(DS172) to list of documentation.

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You may not reproduce, modify, distribute, or publicly display the Materials without prior written consent. Certain products are subject to
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DS160 (v2.0) October 25, 2011 www.xilinx.com

Product Specification 10
 Spartan-6 Family Overview

Spartan-6 FPGA Documentation

Complete and up-to-date documentation of the Spartan-6 family of FPGAs is available on the Xilinx website at
http://www.xilinx.com/support/documentation/spartan-6.htm. In addition to the most recent Spartan-6 Family Overview, the
following files are also available for download:

Spartan-6 FPGA Data Sheet: DC and Switching Spartan-6 FPGA Memory Controller User Guide
Characteristics (DS162) (UG388)
This data sheet contains the DC and Switching This guide describes the Spartan-6 FPGA memory
Characteristic specifications for the Spartan-6 family. controller block, a dedicated, embedded multi-port memory
controller that greatly simplifies interfacing Spartan-6
Spartan-6 FPGA Packaging and Pinout Specifications FPGAs to the most popular memory standards.
(UG385)
Spartan-6 FPGA PCB Design and Pin Planning Guide
These specifications includes the tables for device/package
(UG393)
combinations and maximum I/Os, pin definitions, pinout
tables, pinout diagrams, mechanical drawings, and thermal This guide provides information on PCB design for
specifications. Spartan-6 devices, with a focus on strategies for making
design decisions at the PCB and interface level.
Spartan-6 FPGA Configuration Guide (UG380)
Spartan-6 FPGA Power Management User Guide
This all-encompassing configuration guide includes
(UG394)
chapters on configuration interfaces (serial and parallel),
multi-bitstream management, bitstream encryption, This document provides information on the various
boundary-scan and JTAG configuration, and reconfiguration hardware methods of power management in Spartan-6
techniques. FPGAs, primarily focusing on the suspend mode.

Spartan-6 FPGA SelectIO Resources User Guide XA Spartan-6 Automotive FPGA Family Overview
(UG381) (DS170)
This guide describes the SelectIO™ resources available in This overview outlines the features and product selection of
all the Spartan-6 devices. the Xilinx Automotive (XA) Spartan-6 family.

Spartan-6 FPGA Clocking Resources User Guide Defense-Grade Spartan-6Q Family Overview
(UG382) (DS172)
This guide describes the clocking resources available in all This overview outlines the features and product selection of
Spartan-6 devices, including the DCMs and the PLLs. the Defense-Grade Spartan-6Q family.

Spartan-6 FPGA Block RAM Resources User Guide

(UG383)
This guide describes the Spartan-6 device block RAM
capabilities.

Spartan-6 FPGA Configurable Logic Blocks User Guide

(UG384)
This guide describes the capabilities of the configurable
logic blocks (CLB) available in all Spartan-6 devices.

Spartan-6 FPGA GTP Transceivers User Guide (UG386)

This guide describes the GTP transceivers available in all
the Spartan-6 LXT FPGAs.

Spartan-6 FPGA DSP48A1 Slice User Guide (UG389)

This guide describes the architecture of the DSP48A1 slice
in Spartan-6 FPGAs and provides configuration examples.

DS160 (v2.0) October 25, 2011 www.xilinx.com

Product Specification 11