SNAS805 June   2020 LMK61E08

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Pinout and Simplified Block Diagram
      1.      Device Images
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 6 Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings
    3. 6.3  Recommended Operating Conditions
    4. 6.4  Thermal Information
    5. 6.5  Electrical Characteristics - Power Supply
    6. 6.6  LVPECL Output Characteristics
    7. 6.7  LVDS Output Characteristics
    8. 6.8  HCSL Output Characteristics
    9. 6.9  Frequency Tolerance Characteristics
    10. 6.10 Frequency Margining Characteristics
    11. 6.11 Power-On Reset Characteristics (VDD)
    12. 6.12 I2C-Compatible Interface Characteristics (SDA, SCL)
    13. 6.13 PSRR Characteristics
    14. 6.14 Other Characteristics
    15. 6.15 PLL Clock Output Jitter Characteristics
    16. 6.16 Typical 156.25-MHz Output Phase Noise Characteristics
    17. 6.17 Typical 161.1328125 MHz Output Phase Noise Characteristics
    18. 6.18 Additional Reliability and Qualification
    19. 6.19 Typical Characteristics
  7. 7 Parameter Measurement Information
    1. 7.1 Device Output Configurations
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Device Block-Level Description
      2. 8.3.2  Device Configuration Control
      3. 8.3.3  Register File Reference Convention
      4. 8.3.4  Configuring the PLL
      5. 8.3.5  Integrated Oscillator
      6. 8.3.6  Reference Divider and Doubler
      7. 8.3.7  Phase Frequency Detector
      8. 8.3.8  Feedback Divider (N)
      9. 8.3.9  Fractional Engine
      10. 8.3.10 Charge Pump
      11. 8.3.11 Loop Filter
      12. 8.3.12 VCO Calibration
      13. 8.3.13 High-Speed Output Divider
      14. 8.3.14 High-Speed Clock Output
      15. 8.3.15 Device Status
        1. 8.3.15.1 Loss of Lock
    4. 8.4 Device Functional Modes
      1. 8.4.1 Interface and Control
      2. 8.4.2 DCXO Mode and Frequency Margining
        1. 8.4.2.1 DCXO Mode
        2. 8.4.2.2 Fine Frequency Margining
        3. 8.4.2.3 Coarse Frequency Margining
    5. 8.5 Programming
      1. 8.5.1 I2C Serial Interface
      2. 8.5.2 Block Register Write
      3. 8.5.3 Block Register Read
      4. 8.5.4 Write SRAM
      5. 8.5.5 Write EEPROM
      6. 8.5.6 Read SRAM
      7. 8.5.7 Read EEPROM
    6. 8.6 Register Maps
      1. 8.6.1 Register Descriptions
        1. 8.6.1.1  VNDRID_BY1 Register; R0
        2. 8.6.1.2  VNDRID_BY0 Register; R1
        3. 8.6.1.3  PRODID Register; R2
        4. 8.6.1.4  REVID Register; R3
        5. 8.6.1.5  SLAVEADR Register; R8
        6. 8.6.1.6  EEREV Register; R9
        7. 8.6.1.7  DEV_CTL Register; R10
        8. 8.6.1.8  XO_CAPCTRL_BY1 Register; R16
        9. 8.6.1.9  XO_CAPCTRL_BY0 Register; R17
        10. 8.6.1.10 DIFFCTL Register; R21
        11. 8.6.1.11 OUTDIV_BY1 Register; R22
        12. 8.6.1.12 OUTDIV_BY0 Register; R23
        13. 8.6.1.13 RDIVCMOSCTL Register; R24
        14. 8.6.1.14 PLL_NDIV_BY1 Register; R25
        15. 8.6.1.15 PLL_NDIV_BY0 Register; R26
        16. 8.6.1.16 PLL_FRACNUM_BY2 Register; R27
        17. 8.6.1.17 PLL_FRACNUM_BY1 Register; R28
        18. 8.6.1.18 PLL_FRACNUM_BY0 Register; R29
        19. 8.6.1.19 PLL_FRACDEN_BY2 Register; R30
        20. 8.6.1.20 PLL_FRACDEN_BY1 Register; R31
        21. 8.6.1.21 PLL_FRACDEN_BY0 Register; R32
        22. 8.6.1.22 PLL_MASHCTRL Register; R33
        23. 8.6.1.23 PLL_CTRL0 Register; R34
        24. 8.6.1.24 PLL_CTRL1 Register; R35
        25. 8.6.1.25 PLL_LF_R2 Register; R36
        26. 8.6.1.26 PLL_LF_C1 Register; R37
        27. 8.6.1.27 PLL_LF_R3 Register; R38
        28. 8.6.1.28 PLL_LF_C3 Register; R39
        29. 8.6.1.29 PLL_CALCTRL Register; R42
        30. 8.6.1.30 NVMSCRC Register; R47
        31. 8.6.1.31 NVMCNT Register; R48
        32. 8.6.1.32 NVMCTL Register; R49
        33. 8.6.1.33 NVMLCRC Register; R50
        34. 8.6.1.34 MEMADR Register; R51
        35. 8.6.1.35 NVMDAT Register; R52
        36. 8.6.1.36 RAMDAT Register; R53
        37. 8.6.1.37 NVMUNLK Register; R56
        38. 8.6.1.38 INT_LIVE Register; R66
        39. 8.6.1.39 SWRST Register; R72
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 PLL Loop Filter Design
        2. 9.2.2.2 Spur Mitigation Techniques
          1. 9.2.2.2.1 Phase Detection Spur
          2. 9.2.2.2.2 Integer Boundary Fractional Spur
          3. 9.2.2.2.3 Primary Fractional Spur
          4. 9.2.2.2.4 Sub-Fractional Spur
        3. 9.2.2.3 Device Programming
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
      1. 11.1.1 Ensured Thermal Reliability
      2. 11.1.2 Best Practices for Signal Integrity
      3. 11.1.3 Recommended Solder Reflow Profile
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Documentation
    2. 12.2 Receiving Notification of Documentation Updates
    3. 12.3 Support Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  13. 13Mechanical, Packaging, and Orderable Information
    1. 13.1 Package Option Addendum
      1. 13.1.1 Packaging Information
      2. 13.1.2 Tape and Reel Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

8.3.4 Configuring the PLL

The PLL in LMK61E08 can be configured to accommodate various output frequencies either through I2C programming interface or, in the absence of programming the PLL defaults stored in EEPROM are loaded on power up. The PLL can be configured by setting the Reference Doubler, Integrated PLL Loop Filter, Feedback Divider, and Output Divider. The corresponding register addresses and configurations are detailed in the description section of each block below.

For the PLL to operate in closed-loop mode, the following condition in Equation 1 has to be met.

Equation 1. FVCO = FREF × (D/R) × [(INT + NUM/DEN)]

where

  • FVCO: PLL/VCO Frequency (4.6 GHz to 5.6 GHz)
  • FREF: 50-MHz reference input
  • D: Reference input doubler, 1=Disabled, 2=Enabled
  • R: Reference input divider, 1=Divider bypass, 4=Divide-by-4
  • INT: PLL feedback divider integer value (12 bits, 1 to 4095)
  • NUM: PLL feedback divider fractional numerator value (22 bits, 0 to 4194303)
  • DEN: PLL feedback divider fractional denominator value (22 bits, 1 to 4194303)

On LMK61E08, the output frequency is related to the VCO frequency as given in Equation 2.

Equation 2. FOUT = FVCO / OUTDIV

where

  • OUTDIV: Output divider value (9 bits, 5 to 511)

The output frequency step size for every bit change in the numerator of the PLL fractional feedback divider is given in Equation 3.

Equation 3. STEPSIZE = (FREF × D)/ (R × OUTDIV × DEN)