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Silicon Laboratories SI5322, SI5369, SI5365, SI5366, SI5367, SI5374, SI5375, SI5326, SI5327 12. Si5368

Models: SI5326 SI5319 SI5369 SI5324 SI5367 SI5322 SI5316 SI5327 SI5366 SI5374 SI5325 SI5323 SI5368 SI5365 SI5375

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Si53xx-RM

3.12. Si5368

The Si5368 is a jitter-attenuating precision clock multiplier for applications requiring sub 1 ps rms jitter performance. The Si5368 accepts four clock inputs ranging from 2 kHz to 710 MHz and generates five independent, synchronous clock outputs ranging from 2 kHz to 945 MHz and select frequencies to 1.4 GHz. The device provides virtually any frequency translation combination across this operating range. The Si5368 input clock frequency and clock multiplication ratio are programmable through an I2C or SPI interface. The DSPLL loop bandwidth is digitally programmable from 60 Hz to 8 kHz, providing jitter performance optimization at the application level. Operating from a single 1.8, 2.5, or 3.3 V supply, the Si5368 is ideal for providing clock multiplication and jitter attenuation in high performance timing applications. See "7. Microprocessor Controlled Parts (Si5319, Si5324, Si5325, Si5326, Si5327, Si5367, Si5368, Si5369, Si5374, Si5375)" on page 76 for a complete description.

RATE[1:0]

Xtal or Refclock

XB

XA

3

BYPASS/DSBL2

CKIN_1+

2

÷ N3_1

CKIN_1–

fx

÷ NC1

1

2

CKOUT_1+

CKIN_2+

0

CKOUT_1–

2

÷ N3_2

CKIN_2–

f3

DSPLL®

fOSC

1

CKOUT_2+

CKIN_3+

2

÷ N1_HS

÷ NC2

2

÷ N3_3

0

CKOUT_2–

CKIN_3–

DSBL2/BYPASS

CKIN_4+

2

÷ N3_4

÷ NC3

1

2

CKOUT_3+

CKIN_4–

0

CKOUT_3–

÷ N2

CKOUT_2

DSBL34

FSYNC

÷ NC4

1

2

CKOUT_4+

CKIN_3

LOGIC/

0

CKOUT_4–

CKIN_4

ALIGN

1 0

C1B

1

2

CKOUT_5+

÷ NC5

C2B

FSYNC

0

CKOUT_5–

C3B

DSBL5

INT_ALM

Control

C1A

C2A

CS0_C3A

CS1_C4A

VDD

LOL

GND

CMODE SDA SDO SCL SDI

A[2]/SS

A[1:0]

INC DEC FS ALIGN

RST

Figure 12. Si5368 Clock Multiplier and Jitter Attenuator Block Diagram

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Rev. 0.5

Image 28

Silicon Laboratories SI5322, SI5369, SI5365, SI5366 12. Si5368, Si5368 Clock Multiplier and Jitter Attenuator Block Diagram

Contents

ANY-FREQUENCY Precision Clocks Si53xx-RM Table of Contents Output Clock Drivers Si5375 Free Run Mode High-Speed I/O Si53xx-RM List of Figures Differential Output Example Requiring Attenuation 108 Si53xx-RM List of Tables Si53xx-RM Any-Frequency Precision Clock Product Family Overview Si53xx-RM Product Selection Guide PLL Device Product Selection Guide Si5322/25/65/67Precision Clock Multipliers Wideband Narrowband vs. Wideband Overview Any-Frequency Clock Family Members Si5316 Si5319 Dspll Si5322 Low Jitter Clock Multiplier Block Diagram Si5322 Si5323 Jitter Attenuating Clock Multiplier Block Diagram Si5323 Si5324 Clock Multiplier and Jitter Attenuator Block Diagram Si5324 Si5325 Low Jitter Clock Multiplier Block Diagram Si5325 Si5326 Clock Multiplier and Jitter Attenuator Block Diagram Si5326 Si5327 Clock Multiplier and Jitter Attenuator Block Diagram Si5327 Si5365 Low Jitter Clock Multiplier Block Diagram Si5365 Si5366 Jitter Attenuating Clock Multiplier Block Diagram 10. Si5366 Si5367 Clock Multiplier Block Diagram 11. Si5367 Si5368 Clock Multiplier and Jitter Attenuator Block Diagram 12. Si5368 13. Si5369 14. Si5374/75 Compared to Si5324/19 Si5374 Functional Block Diagram 15. Si5374 Si5375 Functional Block Diagram 16. Si5375 Device Specifications Parameter Symbol Test ConditionRecommended Operating Conditions1 Min Typ Max Unit DC Characteristics CKINn Input Pins Lvpecl 100 Ω Level Lvcmos Input Pins Level Input Pins Lvcmos Output Pins RST SPI Specifications Si5324, Si5325, Si5367, and Si5368 Parameter Symbol Test Conditions Min Typ Max Unit Differential Reference Clock Input Pins XA/XB SDO Frame Synchronization Timing AC Characteristics-All Devices Min Typ Max Units Lvcmos Pins Device Skew PLL Performance Ckopn Jitter Generation Si5316, Si5324, Si5366, Si5368 Jitter Generation Si5322, Si5325, Si5365, Si5367 Thermal Characteristics Parameter Symbol Test Condition Devices Value Unit Any-Frequency Precision Clock Dspll Block Diagram Dspll All Devices Clock Multiplication Clock Multiplication Circuit Jitter Generation PLL PerformanceJitter Transfer Jitter Tolerance Mask/Template Jitter Tolerance Si5316, Si5322, Si5323, Si5365 and Si5366 Key Features Frequency SettingsPin Control Parts Si5316, Si5322, Si5323, Si5365, Si5366 Clock Multiplication Si5316, Si5322, Si5323, Si5365, Si5366 Input Divider Settings Si5316 Bandwidth ValuesCKnDIV N3n Input Divider FRQSEL10 Nominal Frequency Values MHz BW10 Sonet Clock Multiplication Settings FRQTBL=L Clock Multiplication Si5322, Si5323, Si5365, Si5366Fsout MHz Ckconf = FIN MHz Mult Factor All Devices Si5366 Only FOUT MHz Mllm Hlll Hhlh Setting Datacom Clock Multiplication Settings Frqtbl = M, Ckconf =MHz Mult Factor OUT* MHz 125 10/8 x 66/64 161.13 173.37 X 64/66 x 237/255 125 Hhhl Sonet to Datacom Clock Multiplication Settings FIN MHz Mult Factor FOUT* MHz 62.500 125 155.520 15625/15552 156.25 Clock Output Divider Control DIV34 CKOUT3 and CKOUT4 Si5365 and Si5366Lock Detect Si5322 and Si5365 Input-to-Output Skew Si5322 and Si5365 PLL Self-Calibration Si5316, Si5322, and Si5323 Pins and Reset Si5365 and Si5366 Pins and Reset Pin Control Input Clock Control Manual Input Clock Selection Si5365, Si5366, Autosel = L Clock Active Indicators Autosel = M or H Si5322 and Si5323 Clock Active Indicators Autosel = M or H Si5365 and Si5367Input Clock Priority for Auto Switching Si5322, Si5323 Automatic/Manual Clock Selection Input Clock Priority for Auto Switching Si5365, Si5366 Hitless Switching with Phase Build-Out Si5323, Si5366 Recovery from Digital Hold Si5316, Si5323, Si5366 Digital Hold/VCO FreezeFrame Synchronization Si5366 Narrowband Digital Hold Si5316, Si5323, Si5366 Output Phase Adjust Si5323, Si5366 Using Fsout as a Fifth Output Clock Si5366Fsync Realignment Si5366 Including Fsync Inputs in Clock Selection Si5366 Output Signal Format Selection Sfout Fsout Disable Control DblfsOutput Clock Drivers Alarms PLL Bypass ModeDSBL2/BYPASS Pin Settings Alarm Output Logic Equations Frequency Offset Control Fosctl DSPLLsim Configuration Software Device ResetLock Detect Retrigger Time Wideband PLL Divider Settings Si5325, Si5367 Lock Detect Si5325, Si5367 Loop Bandwidth Si5325, Si5367Input to Output Skew Si5325, Si5367 Signal Frequency Limits Dividers and Limits Low Loop Bandwidth Si5324, Si5327, Si5369, Si5374 Loop Bandwidth Si5319, Si5326, Si5368, Si5375Initiating Internal Self-Calibration Ckoutalwayson and Sqical Truth Table Input Clock Configurations Si5367 and Si5368 Input Clock Control Manual Input Clock Selection Si5367, Si5368, Si5369 Active Input ClockRegister Bits CKIN1,2,3,4 inputs CKIN1,3 & CKIN2,4 clock/FSYNC pairs Manual Input Clock Selection Si5324, Si5325, Si5326, Si5374 Ckselreg or CS pin Active Input Clock Input Clock Priority for Auto Switching Selected Clock Free Run Mode Programming Procedure Clock Control Logic in Free Run Mode Free Run Reference Frequency Constraints  While in Free Run Digital Hold Parameters in History Value of M Digital Hold History Delay Digital Hold History Averaging Time VCO Freeze Si5319, Si5325, Si5367, Si5375 Digital Hold versus VCO Freeze Output Phase Adjust Si5326, Si5368 Unlimited Coarse Skew Adjustment Si5326, Si5368Coarse Skew Control Si5326, Si5368 Fine Skew Control Si5326, Si5368 Frame Synchronization Realignment Si5368 and Ckconfigreg = Output Phase Adjust Si5324, Si5327, Si5369, Si5374Independent Skew Si5324, Si5326, Si5368, Si5369, Si5374 Input-to-Output Skew All Devices CKIN3/CKIN4 Frequency Selection Ckconf = CKINn Frequency kHz Divisor Common NC5 Divider Settings Alignment Alarm Trigger ThresholdCKOUT2 Frequency MHz NC5 Divider Setting KHz Fsout Alarm Trigger Threshold Units of T CKOUT2 Using Fsout as a Fifth Output Clock Si5368 Fsync Skew Control Si5368Including Fsync Inputs in Clock Selection Si5368 Fsout Polarity and Pulse Width Control Si5368 Output Signal Format Selection Disabling CKOUTn Loss-of-Signal Validation Times Loss-of-Signal RegistersClock Validation Time LOS Selection FOS Algorithm Si5324, Si5325, Si5326, Si5368, Si5369, Si5374 FOS Reference Clock Selection CLKnRATE RegistersFOS Reference Si5326 Si5368 LOS Si5319, Si5375 Fosen Alarm Output Logic Equations Si5368 and Ckconfigreg = 11.6. C1B, C2B, C3B, Alrmout Si5368 Ckconfigreg = Lock Detect Retrigger Time Lockt Device Interrupts I2C Command Format 13. I2C Serial Microprocessor Interface Serial Microprocessor Interface SPI SPI Command FormatInstructionBYTE0 Address/Data70BYTE1 Default Device Configuration Register Descriptions High-Speed I/O Input Clock Buffers CML/LVDS Termination 1.8, 2.5, 3.3 Output Driver Configuration Typical Output Circuits Disabling Unused Output Driver Output Driver Si5365, Si5366 Si5325, Si5326, Si5367, Si5368 Typical Clock Output Scope Shots Output Format Measurements1,2Name Sfout Pin Sfout Code Single Diff Vocm Vpk-pk Sfout2, Cmos Sfout3, lowSwingLVDS Sfout5, Lvpecl Sfout7, Lvds Cmos External Reference Circuit OSC-P Three-Level 3L Input Pins No External Resistors Parameter Symbol Min Max Three-Level 3L Input Pins With External Resistors Power Supply Typical Power Supply Bypass Network Tqfp Package Packages and Ordering Guide Resonator/External Clock Selection Approved CrystalsXA/XB Reference Sources and Frequencies RATE10 Reference Jitter Fundamental Mode Crystals Reference Drift38.88MHz XO, 38.88MHz CKIN, 38.88MHz Ckout Phase Phase Noise versus f3, 155.52 MHz in, 622.08 MHz outHigh f3 Value Offset Frequency Hz DBc/Hz Noise Reference vs. Output Frequency MHz in, 622.08 MHz out, 696.399 MHz outYellow-696.399 MHz output Blue-622.08 MHz output MHz Out Jitter Bandwidth Yellow, fs RMS Blue, fs RMS High Reference Frequency MHz thru 163 MHz Ext Ref, 155.52 MHz in, 622.08 MHz out MHz thru 180 MHz Ext Ref, 155.52 MHz in, 622.08 MHz out SONETOC192A, 20 kHz to 80 MHzSONETOC192B, 4 MHz to 80 MHz SONETOC192C, 50 kHz to 80 MHz Appendix C-TYPICAL Phase Noise Plots 52 MHz In 622.08 MHz Out Loop BW = 7 Hz, Si5324 44 MHz In 156.25 MHz Out Loop BW = 80 Hz 44 MHz In 156.25 MHz Out Loop BW = 5 Hz, Si5324 130 44 MHz In 491.52 MHz Out Loop BW = 7 Hz, Si5324 08 MHz In 672.16 MHz Out Loop BW = 6.9 kHz 08 MHz In 672.16 MHz Out Loop BW = 100 Hz 25 MHz In 155.52 MHz Out 125 MHz In 644.531 MHz Out Jitter Values for Figure Jitter Bandwidth 644.531 MHz Jitter RMS 125 MHz In 690.569 MHz Out Jitter Values for Figure Jitter Bandwidth 690.569 MHz Jitter RMS 125 MHz In 693.493 MHz Out Jitter Values for Figure Jitter Bandwidth 693.493 MHz Jitter RMS MHz in, 173.371 MHz and 693.493 MHz out DBc/HzOffset Frequency Hz Jitter Values for Figure 685 MHz In 173.371 MHz Out 685 MHz In 693.493 MHz Out DBc/Hz MHz and 156.25MHz in, 622.08 MHz outJitter Bandwidth MHz Input Jitter RMS MHz In 1 GHz Out MHz in, 148.5 MHz out Digital Video HD-SDIJitter Band Appendix D-ALARM Structure Si5368 Alarm Diagram 1 Si5368 Alarm Diagram 2 Si5316 Pullup/Down Si5322 Pullup/DownPin # Si5316 Pull? Pin # Si5322 Pull? Si5323 Pullup/Down Si5319, Si5324, Pullup/DownPin # Si5323 Pull? Pin # Si5326 Pull? Si5326 Pullup/Down Si5325 Pullup/DownPin # Si5325 Pull? Si5327 Pullup/Down Si5365 Pullup/DownPin # Si5327 Pull? Pin # Si5365 Pull? Si5366 Pullup/Down Pin # Si5366 Pull? Si5367 Pullup/Down Si5368 Pullup/DownPin # Si5367 Pull? Pin # Si5368 Pull? Si5374/75 Pullup/Down Si5369 Pullup/DownPin # Si5374/75 Pull? Bypass 622.08 MHz In, 622.08 MHz Out MHz in, 622.08 MHz out Power Supply Noise to Output Transfer Function Power Supply Noise RejectionMHz in, 155.52 MHz out Bandwidth = 110 Hz Clock Input Crosstalk Results Test Conditions Jitter Band MHz MHz out 622.084 MHzOut No crosstalk 155.52 MHz Hz loop KHz loop Clock Input Crosstalk Phase Noise Plots 5 .5 2 1 M H z in , 6 2 2 .0 8 4 M H z o u t Clock Input Crosstalk Detail View 155 .521 MHz in, 622 .084 MHz ou t Clock Input Crosstalk Wideband Comparison 155 .521 M H z in, 622.084 M H z out Clock Input Crosstalk Output of Rohde and Schwartz RF Jitter vs. Output Format 19.44 MHz In, 622.08 MHz Out Spectrum Analyzer Agilent Model E444OAOutput Format vs. Jitter Hz in, 622.08 M Hz out Test Conditions Input Frequency Variation = ±50 ppmMHz External XA-XB Reference Jitter, fs Input Frequency Input Frequency Variation = ±2000 ppm Jitter Values Fmod Fdev Jitter Start RF Gen Si5326 Si5324 MHz in, 622.08 MHz out RF Generator, Si5326, Si5324 No Jitter For Reference RF Generator, Si5326, Si5324 100 Hz Jitter RF Generator, Si5326, Si5324 1 kHz Jitter RF Generator, Si5326, Si5324 10 kHz Jitter Appendix I-Si5374AND Si5375 PCB Layout Recommendations Ground Plane and Reset Output Clock Routing Oscp Oscn Si5374/75 Crosstalk Jitter Values Si5374, Si5375 Crosstalk Test BedJitter, fsec RMS Si5374, Si5375 Dspll a Si5374, Si5375 Dspll B Si5374, Si5375 Dspll C Si5374, Si5375 Dspll D Revision 0.3 to Revision Revision 0.4 to RevisionRevision 0.41 to Revision Revision 0.42 to Revision Rev 179 Contact Information