ECE 448
Lecture 14
Overview of Modern FPGAs
ECE 448 – FPGA and ASIC Design with VHDL
George Mason University
Resources
Clive “Max” Maxfield,
The Design Warrior’s Guide to FPGAs.
ECE 448 – FPGA and ASIC Design with VHDL
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Resources
Xcell Journal
available for FREE on line @
http://www.xilinx.com/publications/xcellonline/
Electronic Engineering Journal
available for FREE by e-mail after subscribing @
http://www.eejournal.com/subscribe
or on the web @
http://www.eejournal.com/design/fpga
ECE 448 – FPGA and ASIC Design with VHDL
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FPGA Vendors
& Families
ECE 448 – FPGA and ASIC Design with VHDL
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Major FPGA Vendors
SRAM-based FPGAs
~ 51% of the market
• Xilinx, Inc.
~ 85%
• Altera Corp. ~ 34% of the market
• Lattice Semiconductor
• Atmel
• Achronix
• Tabula
Flash & antifuse FPGAs
• Actel Corp. (Microsemi SoC Products Group)
• Quick Logic Corp.
ECE 448 – FPGA and ASIC Design with VHDL
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Xilinx FPGA Families
•
•
High-performance families
• Virtex (220 nm)
• Virtex-E, Virtex-EM (180 nm)
• Virtex-II (130 nm)
• Virtex-II PRO (130 nm)
• Virtex-4 (90 nm)
• Virtex-5 (65 nm)
• Virtex-6 (40 nm)
• Virtex-7 (28 nm)
Low Cost Family
• Spartan/XL – derived from XC4000
• Spartan-II – derived from Virtex
• Spartan-IIE – derived from Virtex-E
• Spartan-3 (90 nm)
• Spartan-3E (90 nm) – logic optimized
• Spartan-3A (90 nm) – I/O optimized
• Spartan-3AN (90 nm) – non-volatile,
• Spartan-3A DSP (90 nm) – DSP optimized
• Spartan-6 (45 nm)
• Artix-7 (28 nm)
ECE 448 – FPGA and ASIC Design with VHDL
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Xilinx FPGA Devices
Technology
Low-cost
Highperformance
Virtex 2, 2 Pro
Spartan 3
Virtex 4
120/150 nm
90 nm
65 nm
45 nm
40 nm
Virtex 5
Spartan 6
Virtex 6
Altera FPGA Devices
Technology
Low-cost
Mid-range
130 nm
Cyclone
Highperformanc
e
Stratix
90 nm
Cyclone II
Stratix II
65 nm
Cyclone III
Arria I
Stratix III
40 nm
Cyclone IV
Arria II
Stratix IV
LUTs & ALUTs
ECE 448 – FPGA and ASIC Design with VHDL
4-bit LUTs vs. 6-bit LUTs
6-bit LUTs introduced in Virtex 5
ECE 448 – FPGA and ASIC Design with VHDL
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Major Differences between Xilinx Families
Look-Up Tables
Spartan 3
Virtex 4
Virtex 5, Virtex 6,
Spartan 6
4-input
6-input
Number of CLB slices
per CLB
4
2
Number of LUTs
per CLB slice
2
4
11
Major Differences between Xilinx Families
Spartan 3
Virtex 4
Maximum Single-Port
Memory Size per LUT
16 x 1
Maximum Shift Register
Size per LUT
16 bits
Number of adder
stages per CLB slice
2
Virtex 5, Virtex 6,
Spartan 6
64 x 1
32 bits
4
12
Altera Cyclone III
Logic Element (LE) – Normal Mode
Altera Stratix III
Adaptive Logic Modules (ALM) – Normal Mode
14
FPGA Embedded Resources
ECE 448 – FPGA and ASIC
Design with VHDL
Embedded Multipliers
ECE 448 – FPGA and ASIC
Design with VHDL
Multipliers in Spartan 3
RAM blocks
Multipliers
Logic blocks
The Design Warrior’s Guide to FPGAs
Devices, Tools, and Flows. ISBN 0750676043
Copyright © 2004 Mentor Graphics Corp. (www.mentor.com)
ECE 448 – FPGA and ASIC Design with VHDL
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Number of Multipliers per Spartan 3 Device
19
Combinational and Registered Multiplier
ECE 448 – FPGA and ASIC Design with VHDL
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Dedicated Multiplier Block
ECE 448 – FPGA and ASIC Design with VHDL
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Cyclone II
Embedded Multiplier Block Overview
Each Cyclone II has one to
three columns of embedded
multipliers.
Each embedded multiplier can
be configured to support
 One 18 x 18 multiplier
 Two 9 x 9 multipliers
Number of Embedded Multipliers
Multiplier Block Architecture
Two Multiplier Types
Two 9x9 multiplier
18x18 multiplier
Multiplier Stage
• Signals signa and signb are used to identify the signed and unsigned inputs.
3 Ways to Use Dedicated Hardware
• Three (3) ways to use dedicated
(embedded) hardware
– Inference
– Instantiation
– CoreGen in Xilinx
MegaWizard Plug-In Manager in Altera
28
DSP Units
ECE 448 – FPGA and ASIC
Design with VHDL
Xilinx XtremeDSP
• Starting with Virtex 4 family, Xilinx introduced DSP48 block
for high-speed DSP on FPGAs
• Essentially a multiply-accumulate core with many other
features
• Now also in Spartan-3A, Spartan 6, Virtex 5, and Virtex 6
30
Multiplier-Accumulator - MAC
Multiplier
Adder
Accumulator
A[n:0]
x
B[n:0]
+
MAC
Y[(2n - 1):0]
The Design Warrior’s Guide to FPGAs
Devices, Tools, and Flows. ISBN 0750676043
Copyright © 2004 Mentor Graphics Corp. (www.mentor.com)
31
Mathematical Functions
• DSP 48 can perform mathematical functions such as:
•
•
•
•
•
•
•
•
•
Add/Subtract
Accumulate
Multiply
Multiply-Accumulate
Multiplexer
Barrel Shifter
Counter
Divide (multi-cycle)
Square Root (multi-cycle)
• Can also create filters such as:
•
•
•
•
Serial FIR Filter (Xilinx calls this MACC filters)
Parallel FIR Filter
Semi-Parallel FIR Filter
Multi-rate FIR Filters
32
DSP48 Slice: Virtex 4
33
Simplified Form of DSP48
Adder Out = (Z ± (X + Y + CIN))
34
Choosing Inputs to DSP Adder
P = Adder Out = (Z ± (X + Y + CIN))
35
DSP48E Slice : Virtex5
36
New in Virtex 5 Compared to Virtex 4
37
Xilinx DSP48
38
Stratix III
DSP Unit
Embedded Memories
ECE 448 – FPGA and ASIC
Design with VHDL
Memory Types
Memory
RAM
ROM
Memory
Single port
Dual port
Memory
With asynchronous
read
With synchronous
read
41
Memory Types in Xilinx
Memory
Distributed
(MLUT-based)
Block RAM-based
(BRAM-based)
Memory
Inferred
Instantiated
Manually
Using Core Generator
42
Memory Types in Altera
Memory
Distributed
(ALUT-based,
Stratix III onwards)
Memory block-based
Small size
(512)
Medium size Large size
(4K, 9K, 20K) (144K, 512K)
Memory
Inferred
Instantiated
Manually
Using MegaWizard
Plug-In Manager
43
Cyclone II Memory Blocks
The embedded memory structure consists of columns of M4K
memory blocks that can be configured as RAM, first-in first-out
(FIFO) buffers, and ROM
Memory Modes
The M4K memory blocks support the
following modes:
 Single-port RAM (RAM:1-Port)
 Simple dual-port RAM (RAM: 2-Port)
 True dual-port RAM (RAM:2-Port)
 Tri-port RAM (RAM:3-Port)
 Single-port ROM (ROM:1-Port)
 Dual-port ROM (ROM:2-Port)
Single-Port ROM
• The address lines of the ROM are registered
• The outputs can be registered or unregistered
• A .mif file is used to initialize the ROM contents
Stratix II TriMatrix Memory
Stratix II TriMatrix Memory
Stratix III & Stratix IV TriMatrix Memory
Stratix II & III Shift-Register Memory Configuration
Supply Voltage
ECE 448 – FPGA and ASIC Design with VHDL
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Change in Supply Voltages
Year
1998
1999
2000
2001
2003
2008
2009
2011
Technology (nm)
350
250
180
150
130
65
40
28
ECE 448 – FPGA and ASIC Design with VHDL
Core Supply Voltage (V)
3.3
2.5
1.8
1.5
1.2
1.0
0.9
0.9
52
Gigabit Transceivers
ECE 448 – FPGA and ASIC Design with VHDL
53
Using a Bus to Communicate
Between Devices
n-bit bus
FPGA
Other
device
The Design Warrior’s Guide to FPGAs
Devices, Tools, and Flows. ISBN 0750676043
Copyright © 2004 Mentor Graphics Corp. (www.mentor.com)
54
Using High-Speed Tranceivers to
Communicate Between Devices
Transceiver block
Differential pairs
FPGA
The Design Warrior’s Guide to FPGAs
Devices, Tools, and Flows. ISBN 0750676043
Copyright © 2004 Mentor Graphics Corp. (www.mentor.com)
ECE 448 – FPGA and ASIC Design with VHDL
55
Using High-Speed Tranceivers to
Communicate Between Devices
Transceiver block
FPGA
Transmit (TX) to other device
Receive (RX) from other device
Differential
pairs
The Design Warrior’s Guide to FPGAs
Devices, Tools, and Flows. ISBN 0750676043
Copyright © 2004 Mentor Graphics Corp. (www.mentor.com)
56
Effect of Noise on Single Wire
and Differential Pair
Noise spikes
(a)
Outside
World
FPGA
(b)
1
IN
IN
Standard
Input
RXN
Differential
Pair
0
Noise spikes
RXN 1
RXP
RXP 0
The Design Warrior’s Guide to FPGAs
Devices, Tools, and Flows. ISBN 0750676043
Copyright © 2004 Mentor Graphics Corp. (www.mentor.com)
57
Generating a Differential Pair
Transmitting
Device
Outside
World
TXN
TXP
The Design Warrior’s Guide to FPGAs
Devices, Tools, and Flows. ISBN 0750676043
Copyright © 2004 Mentor Graphics Corp. (www.mentor.com)
58
Multiple Standards for High-Speed Serial
Communication
Fibre Channel
InfiniBand
PCI Express (developed by Intel)
RapidIO
SkyRail (developed by MindSpeed Technologies)
10-gigabit Ethernet
The Design Warrior’s Guide to FPGAs
Devices, Tools, and Flows. ISBN 0750676043
Copyright © 2004 Mentor Graphics Corp. (www.mentor.com)
59
Using FPGA to Interface Between
Multiple Standards
Gigibit interface
standard A
Transceiver
blocks
Gigibit interface
standard B
“Stuff”
Chip A
FPGA
Chip B
The Design Warrior’s Guide to FPGAs
Devices, Tools, and Flows. ISBN 0750676043
Copyright © 2004 Mentor Graphics Corp. (www.mentor.com)
60
Ganging Multiple Transceivers Together
Four gigabit
transceiver
blocks
4x electrical differential
signal TX and RX pairs at
2.5 gigabits/second each
To/from
the main
FPGA fabric
FPGA
Special external
interface chip
Channel bonding
control signals
Optical cable/signal
(10 gigabits/second)
The Design Warrior’s Guide to FPGAs
Devices, Tools, and Flows. ISBN 0750676043
Copyright © 2004 Mentor Graphics Corp. (www.mentor.com)
61
An Ideal Signal vs. Signal Seen by Receiver
1
0
1
0
1
0
1
0
1
Signal sent from
transmitter
Signal “seen”
by receiver
The Design Warrior’s Guide to FPGAs
Devices, Tools, and Flows. ISBN 0750676043
Copyright © 2004 Mentor Graphics Corp. (www.mentor.com)
62
The Effects of Transmitting a Series of
Identical Bits
1
1
1
0
1
0
1
0
1
Signal sent from
transmitter
Signal “seen”
by receiver
The Design Warrior’s Guide to FPGAs
Devices, Tools, and Flows. ISBN 0750676043
Copyright © 2004 Mentor Graphics Corp. (www.mentor.com)
63
Main Elements of the Transceiver Block
8b/10b
Encoder
FIFO
Polarity
flipper
Serializer
TXP
8-bit bus
from main
FPGA fabric
TXN
This is where
pre-emphasis
takes place
Transmitter
FIFO
8b/10b
Deccoder
Polarity
flipper Deserializer
This is where
equalization
takes place
RXP
8-bit bus
to main
FPGA fabric
To
another
device
RXN
From
another
device
Receiver
Transceiver Block
FPGA
The Design Warrior’s Guide to FPGAs
Devices, Tools, and Flows. ISBN 0750676043
Copyright © 2004 Mentor Graphics Corp. (www.mentor.com)
64
Recovering Clock Signal
1
0
1
0
1
0
1
0
1
0
1
0
(a) Simple signal
Real edges
1
1
1
0
0
0
1
0
1
1
0
1
(b) More complex signal
Derived edges
Real edges
65
Sampling the Incoming Signal
Data sample times
Derived edges
Real edges
66
Xilinx ML605 Evaluation Kit
$1795
67
PLDA XpressV6 Design Kit
$3990
68
HiTech Global PCI Express Gen 2 /
SFP+ / USB 3.0 Development Board
$2995
69
HiTech Global HXT 8-lane PCI Express/4port SFP+ Optical Network Card
$8995
70
HiTech Global HXT 16-lane PCI
Express Optical Network Card
$8995
71
Altera Stratix IV GX FPGA
Development Kit
$4495
72
PLDA XpressGX4LP Design Kit
$4990
73
HiTech Global GT/GX PCI Express Gen 2 / 3 &
Optical Development Platform/Networking Card
$5995
74
Terasic DE4 Development and
Education Board
$2995
75
Gutz Logic PCI Express x1 Demo Board
(Actel FPGA)
76
LatticeSC PCI Express x4 Evaluation
77
Board Overview
Manufacturer
Name
FPGA
Memory
Application
PCIe
Throughput
Base Price
Boards based on Xilinx Virtex-6
Xilinx
ML605 Evaluation Kit
LX240T-1
2GB (max)
General Purpose
1.1 x8 / 2.0 x4
2 GB/s
$1795
PLDA
XpressV6 Design Kit
LX550T (max)
8GB (max)
General Purpose
2.0 x8
4 GB/s
$3990
HiTech Global
PCI Express / USB 3.0
LX550T (max)
8GB (max)
General Purpose
2.0 x8
4 GB/s
$2995
HiTech Global
HXT 8-lane Optical
HX565T (max)
16GB (max)
High Speed Eth.
2.0 x8
4 GB/s
$8995
HiTech Global
HXT 16-lane Optical
HX565T (max)
16GB (max)
High Speed Eth.
2.0 x16
8 GB/s
$8995
Boards based on Altera Stratix IV
Altera
Stratix IV GX Kit
GX530 (max)
512MB
General Purpose
2.0 x8
4 GB/s
$4495
PLDA
XpressGX4LP
GX530 (max)
2GB (max)
High Speed Eth.
2.0 x8
4 GB/s
$4990
HiTech Global
GT/GX PCIe & Optical
100G5 (max)
4GB (max)
High Speed Eth.
3.0 x8
8 GB/s
$5995
Terasic
DE4 Board
GX530 (max)
8GB (max)
General Purpose
2.0 x8
4 GB/s
$2995
A3P1000
1MB
PCIe Evaluation
1.1 x1
250 MB/s
N/A
32MB
PCIe Evaluation
1.1 x4
1 GB/s
N/A
Boards based on Actel ProASIC3
Gutz Logic
PCI e x1 Demo Board
Boards based on Lattice Semiconductor LatticeSC
Lattice
LatticeSC PCIe x4 Board
ECP2M-50
78
Embedded Microprocessors
ECE 448 – FPGA and ASIC Design with VHDL
79
Embedded Microprocessor Cores
uP
uP
uP
uP
uP
(a) One embedded core
(b) Four embedded cores
The Design Warrior’s Guide to FPGAs
Devices, Tools, and Flows. ISBN 0750676043
Copyright © 2004 Mentor Graphics Corp. (www.mentor.com)
ECE 448 – FPGA and ASIC Design with VHDL
80
Virtex-II Pro Architecture
2
3
Features:
1.
2.
3.
4.
5.
6.
Processor Block
RocketIO Multi-Gigabit
Transceivers
CLB and Configurable Logic
SelectIO-Ultra
Digital Clock Managers
Multipliers and Block
SelectRAM
1
6
4
ECE 448 – FPGA and ASIC Design with VHDL
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81
ECE 448 – FPGA and ASIC Design with VHDL
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PowerPC Cores
PowerPC
System
PowerPC
System
ECE 448 – FPGA and ASIC Design with VHDL
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Embedded Development Kit (EDK)
Software Flow
Hardware Flow
Processor IP,
Microprocessor
Peripheral
Description Files
VHDL /
Verilog
C / C++
Code
Libraries
PlatGen
Synthesizer
Compiler
LibGen
Microprocessor
Hardware
Specification
File
EDIF IP
Netlists
Object Files
Microprocessor
Software
Specification File
ISE /
Xflow
Linker
System
Constraint
File
Bitstream
Data2MEM
Executable
Download to FPGA
ECE 448 – FPGA and ASIC Design with VHDL
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Zynq - Extensible Processing Platform
ECE 448 – FPGA and ASIC Design with VHDL
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Zynq – 7000 EPP
ECE 448 – FPGA and ASIC Design with VHDL
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Zynq – 7000 Product Table
ECE 448 – FPGA and ASIC Design with VHDL
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