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Top 10 Signaling Challenges (and Solutions) Presentation by drr53761

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									SigCon Top
      John Goldie
        Webinar
     February 2009
       Top     10 Signal Conditioning Tips
W
    1 – PowerSaver Equalizers – DS38EP100/DS80EP100 – Life Extender
E
    2 – HDMI Active Equalizer – DS16EV5110A – Reach Extender
B
    3 – PCIe Active Equalizer – DS50EV401 – Reach Extender
I
    4 – Video Link (Ser/Des) Extender – DS15BA/EA101 – Link Extender
N
    5 – Maximum Length Drive & Fr4 losses – DS25BR100 – Reach Extender
A
    6 – 10G Interconnects & Stubs and other things that matter!
R
    APPENDIX
    7 – Redundancy & SigCon Mux-Buffers – DS40MB200 – Flexibility & Reach
    8 – Signal Routing in SMPTE – DS25CP104A – Functionality & Reach
    9 – XAUI CAT 6 & 7 Driving – DS42BR400 – Eye Opening Reach
    10 – TCA - MLVDS Failsafe & edge rate – DS91C176 – Quality and Topography
    Reference
    Rapidesigner
    Contact Information
     Today’s Topic is Signal Conditioning

         Inter Symbol Interference (ISI) and LOSS
Single
Ended
Signal




                 0   1   0   1   1   1   1   0   1
      Today’s Topic is Signal Conditioning

       Inter Symbol Interference (ISI) and LOSS




Differential   0   1   0   1   1   1   1   0   1
Signal
      Today’s Topic is Signal Conditioning

       Inter Symbol Interference (ISI) and LOSS




Differential        0    1    0     1    1    1     1    0     1
Signal




                       Real World Differential Signal
         Eye pattern is the collection of many overlaying patterns
      Today’s Topic is Signal Conditioning

       Inter Symbol Interference (ISI) and LOSS




Differential        0    1    0     1    1    1     1    0     1
Signal




                                                                     Effect
                       Real World Differential Signal                of ISI
         Eye pattern is the collection of many overlaying patterns
      Today’s Topic is Signal Conditioning

       Inter Symbol Interference (ISI) and LOSS




Differential        0    1    0     1    1    1     1    0     1
Signal




                                                                     Effect
                       Real World Differential Signal                of ISI
         Eye pattern is the collection of many overlaying patterns
1    How to extend a chassis’ life?

                             • Loss is a function of Channel
Tx        Channel       Rx     –   Trace (FR4, 6mil, microstrip)
                               –   Via
                               –   Connectors
5 Gbps                         –   Data Rate

                             • Doubling of Data Rate
      Double the Data
       Rate and the          • Life Extension of H/W
        Eye closes!          • But Eye is closed
                               – Jitter
10 Gbps                        – Amplitude

                             • Open the EYE with a
                               PowerSaver Equalizer
                               Solution
1                    PowerSaver Equalizers – EP Family
                                                                          • DS38EP100 (2 to 5Gbps)
Tx                             Channel                       EP Rx        • DS80EP100 (5 to 12.5Gbps)
                                                                          • EPs can be located at ANY point
                                                                            in the path
Tx                   EP                  Channel                     Rx   • Small Size (2.2mm x 2.5mm)
                                                                          • No Power or GND connection
                                                                            required!
Tx                       Channel EP                   Channel        Rx
                                                                          • Works with CML, LVPECL, or
                                                                            LVDS signaling
                               EP Transfer Function

                     0     2         4           6       8      10
                                                                          • Works with any codes: 8b10b,
                0
                -1
                                                                            scrambled, DC….
                -2
                -3
                                                                          • Bi-directional
                                         DS80EP100
     S21 (dB)




                -4

                -5
                                                                          • Economical boost solution that
                                         DS38EP100
                -6
                -7
                                                                            extends the life of a unit!
                -8
                -9
                                    Frequency (GHz)
1      EP Design Considerations
       Without EP               With EP
                                          • PowerSaver Equalizers reduce jitter
        High                                and open the eye – provides a De-
                                            Emphasis function
 5
Gbps                                      • Will attenuate the signal (8dB)
                              EYE OPEN       – Must meet RX minimum sensitivity
       Jitter                                  requirement
                         EP                  – TX optimization – increase VOD
        100%                                   (1Vpp) or use Pre-Emphasis – De-
                                               Emphasis not recommended
 10                                          – Can work with Active EQs
Gbps                                           Can stack / watch attenuation
                              EYE OPEN    • DS38EP100 targeted at:
        Jitter
                                             – 2 to 5Gbps
                DS80EP100                    – 40” FR4 6mil microstrip or other
                                          • DS80EP100 targeted at:
                                             – 5 to 12Gbps
                                             – 20” FR4 6mil microstrip or other
                    2X

                                          Extends the Data Rate or
                                          Extends the Reach
2     How to Extend an HDMI Cable……….or
      How to use a smaller more flexible cable.
• Typical HDMI cables          • What do I do if I want to go
    – 24 AWG / 5 meters          longer distance?
    – 28 AWG / 2 meters
                               • How to use a smaller, more
• Typical Clock / Line Rates     flexible, more economical
    – 75MHz / 750Mbps            cables with higher losses?
                                 (30 or 32 AWG)
       • 720p @ 8bpp
    – 150MHz / 1.5Gbps
       • 1080p @ 8bpp          • How do I utilize installed
    – 225 MHz / 2.25Gbps         Cat5 cables? (code, in wall,
       • 1080p @ 12bpp
                                 economical)

                               • Open the eye and extend the
                                 reach with an Active
                                 Equalizer
2           DS16EV5110A HDMI
            Active Equalizer (EV)
                        3V3                                        VDD                              VDD                                  3V3
                         10 μF                                              DS16EV5110A                               10 μF
                                                                   VDD
                                                                             HDMI / DVI             VDD
                                                                                                                       All Bypass CAPS
                                                                                                                     0.1 μF unless noted.
                                                                   VDD      EQUALIZER               VDD

                                                                                                    VDD
                                                                                                                                                                                                                                 <5 Native Ser/Des
H
                                                          C_IN+                                            C_OUT+
        Clock                                                                                                                                                                                              Clock




                                                                                                                                               TMDS OUTPUT PORT - 4 CHANNEL
                           TMDS INPUT PORT - 4 CHANNEL




         Clock                                            C_IN-                  LA          CD            C_OUT-                                                                                           Clock
                                                                                                                                                                                                                                  <10m PowerSaver EQ




                                                                                                                                                                              DC Couple 50 Ω Termination
D
                                                         D_IN0+                                            D_OUT0+


                                                         D_IN0-                  EQ          CD            D_OUT0-


                                                         D_IN1+                                            D_OUT1+
                                                                                                                                                                                                                                       >20m     Active EQ
M                                                         D_IN1-


                                                         D_IN2+
                                                                                 EQ          CD            D_OUT1-

                                                                                                           D_OUT2+


I                                                        D_IN2-                  EQ          CD            D_OUT2-
                                                                                                                                                                                                                                Cable length
                                                                   BST_0                             SD
                 Equalization
                   Control
                    Input




                                                                   BST_1




                                                                                                                       Optional SM Bus
                                                                   BST_2                            SDA

                                                                                                    SDC


                                                                   FEB                               CS
                                                                                                                                                                                                               REDUCE Jitter
                         Control




                                                                   EN                             Reserv

                                                                                                                                                                                                               RESTORE Amplitude
                                                                           GND




                                                                                      DAP




                                                                                       GND

                                                                                                               Cable Output after 25m                                                                                    Equalized Eye after
    Input to Cable
    Input to cable                                                                                             28AWG DVI Cable, 1.65Gbps                                                                                 DS16EV5110A




                                                                                 >20m                                                                                                                               EV
                                                                                                                                                                                                                                               To
                                                                                                                                                                                                                                               DES
2           DS16EV5110A HDMI
            Design Considerations
• >40 meters 24 AWG DVI (1.65Gbps)             • 8 levels of Equalization
• >20 meters 28 AWG DVI (1.65Gbps)                – Pin Setable or SMBus (opt)
• >20 meters Cat5/5e/6 cable (1.65Gbps)        • DC Coupled (TMDS) Interface
• >20 meters 28 AWG HDMI (2.25Gbps)            • 250Mbps to 2.25Gbps (per lane)
                                               • 3D+C configuration – HDMI Optimized
                            See                • Signal Detect Output – tie to Enable
                            AN-1613              for Power Saver
                                               • Tj < 0.2 UI @ 1.65Gbps / 25m / 28AWG
    Setting    Data Rate    28 AWG Cable       • Rugged >6kV HBM ESD Tolerance
    BST[2:0]   (per lane)   STP DVI/HDMI
                                               • Meets HDMI Source and Sink
     0x04      750 Mbps     0 to 25 meters       requirements (1.3a)
     0x04      1.65 Gbps    0 to 20 meters
                                               • Use in Source, Sink or Repeater
     0x06      750 Mbps     25 to >30 meters     Applications
     0x06      1.65 Gbps    20 to >25 meters
     0x03      2.25 Gbps    0 to 15 meters
                                               Ease of Use – Plug and Go not….
     0x06      2.25 Gbps    15 to >20 meters
                                                Plug and Pray
3   How to extend PCIe Interconnects

                     • What do I do if I want to go
                       longer distance interconnect?

                     • How do I extend the life of a
                       Gen 1 or Gen 2 hardware?

                     • How do I support the next
                       Generation of data rates?

                     • Open the eye and extend the
                       reach with an Active Equalizer
3     Active Variable Equalizers
      DS50EV401 (PRBS7 pattern)
Without EQ         With EQ                  Without EQ         With EQ

                                  Gen1
                                  2.5G



                                  Gen2
                                  5.0G
             40”                                         10m
             30”                                         7m

                                  Gen3
                                  8.0G

     BACKPLANE / FR4                             CABLE TWINAX (24AWG)
                       “A picture is worth a thousand
                        words!” - Here’s 12K words!
3      DS50EV401 PCIe Equalizer
       Design Considerations
• Gen 1 / Gen 2 Mode (Mode = H)           • 2.5 / 5.0 Gbps or 8 Gbps mode
    – Up to 40” FR4 / 6mil / microstrip      – Simple Mode Pin control
    – Up to 10m 24 AWG Twinax
                                          • 4 independent Channels
        • 20 dB @ 2.5 Gbps
        • 14 dB @ 5.0 Gbps
                                             – Separate Enable and Signal Detect
                                               Pins
• Gen 3 Mode (Mode = L)                   • Passes BEACON signal
    – Up to 30” FR4 / 6mil / microstrip      – Used as wake up, low freq.
    – Up to 7m 24 AWG Twinax              • Supports TX Idle state
        • 16 dB @ 8.0 Gbps
                                          • AC Coupled CML signaling
• Use PRBS7 to represent 8b/10b           • Tj < 0.2 UI
• 75-200nF Caps at TX side                • 3.3V or 2.5V Power option
• Lane = Out & In pair                    • Use at Load end (Near RX)
                                          • Cable or Backplane Applications
                                          Watch for new PCIe parts soon!
4        How to extend a Serial Link?
         What CAT Cable to use?


           t                                                     t
      - bi                                                  - bi
    18 GB                                                 18 GB
      R                       <10m                          R




     • How do I extend the a serial link from a few meters to
       many meters?
     • How can I use low cost CAT cable instead of a expensive
       thick video cable?
4         What CAT Cable?
4 twisted pairs, solid or stranded, 100 Ohm,                                                      CAT5e        CAT6          CAT6A     CAT7      CAT7A

low cost, mainly UTP, common networking                                             0

                                                                                  -0.1

CAT    Type   Speed   Application      Notes                                      -0.2




                                                             Attenuation [dB/m]
 #            (MHz)                                                               -0.3

                                                                                  -0.4
 1     UTP     Low    POTS
                                                                                  -0.5

                                                                                  -0.6
 2     UTP      4     Token Ring                                                  -0.7

                                                                                  -0.8
 3     UTP     16     10 enet                                                     -0.9
                                                                                         1                10                           100               1000
                                                                                                                 Frequency [MHz]
 4     UTP     20     Token Ring (16
                      MHz)                                                                            CAT5e           CAT6      CAT7     CAT7A

 5     UTP     100    10/100 enet                                                 70
                      (Obsolete)
                                                                                  60

 5e    UTP     100    10/100/1000      Improved for NEXT                          50
 (D)                                   and others over “5”




                                                                     NEXT [dB]
                                                                                  40
  6    UTP     250    1000BaseT        Overall Foil Shield
                                                                                  30
 (E)                                   & Spacer
                                                                                  20
 6a    UTP     500    10GBaseT
(EA)                                                                              10

  7    STP     600    10GBaseT         Foil Shielded Pairs                          0
 (F)                                                                                     1                10                           100               1000
                                                                                                                 Frequency [MHz]
 7a    STP    1000    10GBaseT         Shielded Pairs
(FA)
                                                                                             Other Pair usage? NEXT…..
4   Link Extender Application Diagram using a
    Line Driver & Adaptive Equalizer


                     Good Eye                OPEN
                                              EYE




      1          2              3        4          5

                                                1 – Reduce wire count
                                                2 – Level shift
          CAT5e/6/7                             3 – Reach & Loss
          or Coax                   NO EYE      4 – Recover
                                                5 – Restore // Bus
4      BA/EA Design Considerations
                                           • Line Driver – Fixed Amplitude
                                           • Line Driver – Fixed Amplitude
                                             Output – DS15BA101
                                             Output – DS15BA101
                                 See         – Set for 400mV (800mVpp) swing
                                             – Set for 400mV (800mVpp) swing
                                 AN-1826       (100 Ohm) – external R
                                               (100 Ohm) – external R
                                             – Set for 800mV swing (50 Ohm) –
                                             – Set for 800mV swing (50 Ohm) –
                                               external R
                                               external R
                                           • Adaptive Equalizer – automatic
                                           • Adaptive Equalizer – automatic
                                             – DS15EA101
                                             – DS15EA101
                                             –
                                             –   Up to 35dB Boost at 750MHz!
                                                 Up to 35dB Boost at 750MHz!
                                             –
                                             –   High Gain, Noise sensitive
                                                 High Gain, Noise sensitive


• AC Coupled for isolation                 • Ideal for extending FPD-Link II
                                           • Ideal for extending FPD-Link II
  (requires DC Balance)                      buses (DS92UR241/124 Ser/Des)
                                             buses (DS92UR241/124 Ser/Des)
• Budget Crosstalk (35dB gain total)
      • UTP (Single)   35dB                1.5Gbps rates @ many meters
                                           1.5Gbps rates @ many meters
      • UTP (Full Duplex)  C35dB – XTalk   Gigabits @ many meters!
                                           Gigabits @ many meters!
      • STP    35 dB
5   How to get the maximum length?
• How to get the maximum        • DS25BR100 – Buffer/Repeater
  length?                          – Pre-E on LVDS Driver (4 levels)
                                     – EQ on Differential Receiver (4 levels)
                                •   DS25BR110 - EQ + Buffer
• Use to buffer or boost weak   •   DS25BR120 – Buffer w/Pre-E Driver
  ASIC / FPGA outputs that      •   DS25BR150 – Buffer
  wont go the distance!         •   DS10BR150 – 1G Buffer
                                     – Slower transition times

                    PE          • Drive Cables & Traces
                                • Midplane Repeating counteracts via and
                                  long trace routes
                       EQ
                                • Pre-Emphasis –
                                   – Get more swing to start with
                                   – Noise friendly at RX, Noise margin
                                      remains high
                                   – RX MIN input sensitivity easily met
                                • EQ
                                   – Lower power option for signal recovery
                                           – Noise sensitive (12dB)
5       Transmit Signal Conditioning
        Explained
    Pre-Emphasis (Pre-E) vs De-Emphasis (De-E) Waveforms


    Output Pre-Emphasis                                         Output De-Emphasis
                 9 dB

                 6 dB

                 3 dB

                 0 dB
                               Vlow       Vhigh




             PE (dB) = 20Log(Vhigh/Vlow)

                        DS25BR120 Simulation                    DE (dB) = 20Log(VODPEn/VODB)

0   1    0   1      1      1          1     1      DATA     1           1         0        0
                                                  PATTERN
                    Pre-E Tends to be                       De-E Tends to be
                    used with LVDS                          used with CML
5     Where does LOSS come from?
      FR4 Loss vs Length vs Frequency
                                                           f (MHz)
                                       0       500      1000     1500   2000        2500

           5    8    5
                                  0
                5
                8                 -2

          Cross Section
                                  -4
                                                                               14 inches FR4
EVK                       Loss    -6
                           dB
                                  -8


                                 -10                                           28 inches FR4
                                 -12
                                           FR4 Edge Coupled
                                           100 Ohm Stripline
                                 -14
                                                                               42 inches FR4
                                 -16
       Test Traces



       • Loss proportional to SQRT(f) (copper losses)
         and f (dielectric losses)
       • Depends on transmission line geometries
       • Depends on material properties
5     74 inches FR4 @ 2Gbps
      BR Design Considerations
                74 inches FR4, 100 Ohm 5 mil Stripline @ 3.125 Gbps DS25BR110

         SER                                                       EQ    D      DES



• Straight forward
• Buffer / Repeater Function                    After Channel
• SigCon setting depends on
  media (loss) and Rate
    – 2.5Gbps
       • Use 1.25GHz
       • S21 Insertion Loss, match,                              Wide
         experiment                                              Open
       • Pin settable                                            EYEAfter EQ
• Part Placement
                                                                        16 dB
    – One device, two devices
    – TX, Middle, RX
6      How do I go 10Gbps?
                                 Complex BGA routing
• 10 Gbps design (8-12.5)                                                                               Multiple Connectors
                                                                   Card VIA(s)
  is coming!
• Purpose Interconnect                               FR4
                                                     board trace              Driver
                                                                                             ¼ of DS100ME401
                                                                                            Limiting
                                                                                                                        Backplane

                                                                      OUT+                  Amp                IN+
                                               RX+

    – Better Materials               ASIC/
                                               RX-
                                                                      OUT-
                                                                                                       EQ      IN-

                                                                                DE                      EQS
                                     SerDes
    – System Partitioning..                    TX+
                                               TX-

      Midplane division
                                 Line Card
    – Better Structures                                      End-to-End too long!
    – Impedance match                                                                        ¼ of DS100ME401
                                                     FR4
                                                                                            Limiting
    – Parasitics to counteract                 RX+
                                                     board trace
                                                                      OUT+
                                                                              Driver        Amp

                                                                                                       EQ
                                                                                                               IN+
                                                                                                               IN-

      un-avoidables                   ASIC/
                                               RX-
                                                                       OUT-            DE               EQS
                                      SerDes
                                               TX+
                                               TX-



• Deploy Transmit                Switch Card

  Equalization & Receive
                                                                                                            Thick B/P Via
  Equalization                Long Runs on card
6    10G EYEs vs Media and vs Via Stub


 10Gbps
100ps UI!

                  10G, EQ=5, TJ=0.26           10G, EQ=7, TJ=0.33
                 30” 5mil FR4 Stripline        7m 30AWG Twin-Ax




                                                                         Full Amplitude
                                                                         Fast Edge
                                                                         Low Jitter

                 10G, EQ=5, TJ=0.29             10G, EQ=5, TJ=0.32
            Molex B/P 1m BP w/0.2mm Stub   Molex B/P 1mBP w/1.3mm Stub
6                      10G Design Considerations
                       Stubs matter
                                                  Molex iTrac Backplane
                                                                                                                                   Zo
            0


            -5
                                                                                                                     1m BP & 0.1mm Stub
           -10


           -15

                                                                                                     0.38m_0.1stud
           -20                                                                                       0.6m_0.1stud
                                                                                                     1m_0.1stud
SDD21 dB




                                                                                                     0.38m_2.4stud
           -25
                                                                                                     0.6m_2.4stud
                                                                                                     1m_0.6stud                   stub
           -30                                                                                       1m_1.3stud
                                          1m vs stub                                                 1m_5.5stud
           -35


           -40
                                                                                                                                 Zo
           -45


           -50
                 0   1000   2000   3000   4000       5000        6000   7000   8000   9000   10000
                                                                                                               1m BP & 5.5mm Stub
                                                 Frequency MHz




                                                            Stubs Happens!
        Thank you
    for attending our
SigCon Top 10 session
     (Tips 1 to 6)
          APPENDIX
      Tips 7, 8, 9 and 10,
      References & Tools
Contact Information

• John Goldie
  Applications Engineering
  High Speed Data Path / Interface
  High Speed products Division
  Santa Clara, California

 John.Goldie@nsc.com

 408 721 2075 (o)

								
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