SNAS597C July   2012  – January 2016 LMK04816

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  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
    6. 6.6 Timing Requirements
    7. 6.7 Typical Characteristics: Clock Output AC Charcteristics
  7. Parameter Measurement Information
    1. 7.1 Charge Pump Current Specification Definitions
      1. 7.1.1 Charge-Pump Output Current Magnitude Variation vs Charge-Pump Output Voltage
      2. 7.1.2 Charge-Pump Sink Current vs Charge-Pump Output Source Current Mismatch
      3. 7.1.3 Charge-Pump Output Current Magnitude Variation vs Temperature
    2. 7.2 Differential Voltage Measurement Terminology
  8. Detailed Description
    1. 8.1 Overview
      1. 8.1.1  System Architecture
      2. 8.1.2  PLL1 Redundant Reference Inputs (CLKin0/CLKin0*, CLKin1/CLKin1*, and CLKin2/CLKin2*)
      3. 8.1.3  PLL1 Tunable Crystal Support
      4. 8.1.4  VCXO and CRYSTAL-Buffered Outputs
      5. 8.1.5  Frequency Holdover
      6. 8.1.6  Integrated Loop Filter Poles
      7. 8.1.7  Internal VCO
      8. 8.1.8  External VCO Mode
      9. 8.1.9  Clock Distribution
        1. 8.1.9.1 CLKout Divider
        2. 8.1.9.2 CLKout Delay
        3. 8.1.9.3 Programmable Output Type
        4. 8.1.9.4 Clock Output Synchronization
      10. 8.1.10 0-Delay
      11. 8.1.11 Default Start-Up Clocks
      12. 8.1.12 Status Pins
      13. 8.1.13 Register Readback
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Serial MICROWIRE Timing Diagram
      2. 8.3.2  Advanced MICROWIRE Timing Diagrams
        1. 8.3.2.1 Three Extra Clocks or Double Program
        2. 8.3.2.2 Three Extra Clocks with LEuWire High
        3. 8.3.2.3 Readback
      3. 8.3.3  Inputs and Outputs
        1. 8.3.3.1 PLL1 Reference Inputs (CLKin0, CLKin1, and CLKin2)
        2. 8.3.3.2 PLL2 OSCin and OSCin* Port
        3. 8.3.3.3 Crystal Oscillator
      4. 8.3.4  Input Clock Switching
        1. 8.3.4.1 Input Clock Switching - Manual Mode
        2. 8.3.4.2 Input Clock Switching - Pin Select Mode
          1. 8.3.4.2.1 Pin Select Mode and Host
          2. 8.3.4.2.2 Switch Event Without Holdover
          3. 8.3.4.2.3 Switch Event With Holdover
        3. 8.3.4.3 Input Clock Switching - Automatic Mode
        4. 8.3.4.4 Input Clock Switching - Automatic Mode With Pin Select
      5. 8.3.5  Holdover Mode
        1. 8.3.5.1 Enable Holdover
        2. 8.3.5.2 Entering Holdover
        3. 8.3.5.3 During Holdover
        4. 8.3.5.4 Exiting holdover
        5. 8.3.5.5 Holdover Frequency Accuracy and DAC Performance
        6. 8.3.5.6 Holdover Mode - Automatic Exit of Holdover
      6. 8.3.6  PLLs
        1. 8.3.6.1 PLL1
        2. 8.3.6.2 PLL2
          1. 8.3.6.2.1 PLL2 Frequency Doubler
        3. 8.3.6.3 Digital Lock Detect
      7. 8.3.7  Status Pins
        1. 8.3.7.1 Logic Low
        2. 8.3.7.2 Digital Lock Detect
        3. 8.3.7.3 Holdover Status
        4. 8.3.7.4 DAC
        5. 8.3.7.5 PLL Divider Outputs
        6. 8.3.7.6 CLKinX_LOS
        7. 8.3.7.7 CLKinX Selected
        8. 8.3.7.8 MICROWIRE Readback
      8. 8.3.8  VCO
      9. 8.3.9  Clock Distribution
        1. 8.3.9.1 Fixed Digital Delay
          1. 8.3.9.1.1 Fixed Digital Delay - Example
        2. 8.3.9.2 Clock Output Synchronization (SYNC)
          1. 8.3.9.2.1 Effect of SYNC
          2. 8.3.9.2.2 Methods of Generating SYNC
          3. 8.3.9.2.3 Avoiding Clock Output Interruption due to SYNC
          4. 8.3.9.2.4 SYNC Timing
          5. 8.3.9.2.5 Dynamically Programming Digital Delay
            1. 8.3.9.2.5.1 Absolute versus Relative Dynamic Digital Delay
            2. 8.3.9.2.5.2 Dynamic Digital Delay and 0-Delay Mode
            3. 8.3.9.2.5.3 SYNC and Minimum Step Size
            4. 8.3.9.2.5.4 Programming Overview
            5. 8.3.9.2.5.5 Internal Dynamic Digital Delay Timing
            6. 8.3.9.2.5.6 Other Timing Requirements
            7. 8.3.9.2.5.7 Absolute Dynamic Digital Delay
              1. 8.3.9.2.5.7.1 Absolute Dynamic Digital Delay - Example
            8. 8.3.9.2.5.8 Relative Dynamic Digital Delay
              1. 8.3.9.2.5.8.1 Relative Dynamic Digital Delay - Example
      10. 8.3.10 0-Delay Mode
    4. 8.4 Device Functional Modes
      1. 8.4.1 Mode Selection
      2. 8.4.2 Operating Modes
        1. 8.4.2.1 Dual PLL
        2. 8.4.2.2 0-Delay Dual PLL
        3. 8.4.2.3 Single PLL
        4. 8.4.2.4 0-delay Single PLL
        5. 8.4.2.5 Clock Distribution
    5. 8.5 Programming
      1. 8.5.1 Special Programming Case for R0 to R5 for CLKoutX_Y_DIV and CLKoutX_Y_DDLY
        1. 8.5.1.1 Example
      2. 8.5.2 Recommended Programming Sequence
        1. 8.5.2.1 Overview
      3. 8.5.3 Readback
        1. 8.5.3.1 Readback - Example
    6. 8.6 Register Maps
      1. 8.6.1 Register Map and Readback Register Map
      2. 8.6.2 Default Device Register Settings After Power On Reset
      3. 8.6.3 Register Descriptions
        1. 8.6.3.1  Registers R0 to R5
          1. 8.6.3.1.1 CLKoutX_Y_PD, Powerdown CLKoutX_Y Output Path
          2. 8.6.3.1.2 CLKoutX_Y_OSCin_Sel, Clock group source
          3. 8.6.3.1.3 CLKoutY_ADLY_SEL[29], CLKoutX_ADLY_SEL[28], Select Analog Delay
          4. 8.6.3.1.4 CLKoutX_Y_DDLY, Clock Channel Digital Delay
          5. 8.6.3.1.5 RESET
          6. 8.6.3.1.6 POWERDOWN
          7. 8.6.3.1.7 CLKoutX_Y_HS, Digital Delay Half Shift
          8. 8.6.3.1.8 CLKoutX_Y_DIV, Clock Output Divide
        2. 8.6.3.2  Registers R6 TO R8
          1. 8.6.3.2.1 CLKoutX_TYPE
          2. 8.6.3.2.2 CLKoutX_Y_ADLY
        3. 8.6.3.3  Register R10
          1. 8.6.3.3.1 OSCout0_TYPE
          2. 8.6.3.3.2 EN_OSCout0, OSCout0 Output Enable
          3. 8.6.3.3.3 OSCout0_MUX, Clock Output Mux
          4. 8.6.3.3.4 PD_OSCin, OSCin Powerdown Control
          5. 8.6.3.3.5 OSCout_DIV, Oscillator Output Divide
          6. 8.6.3.3.6 VCO_MUX
          7. 8.6.3.3.7 EN_FEEDBACK_MUX
          8. 8.6.3.3.8 VCO_DIV, VCO Divider
          9. 8.6.3.3.9 FEEDBACK_MUX
        4. 8.6.3.4  Register R11
          1. 8.6.3.4.1 MODE: Device Mode
          2. 8.6.3.4.2 EN_SYNC, Enable Synchronization
          3. 8.6.3.4.3 NO_SYNC_CLKoutX_Y
          4. 8.6.3.4.4 SYNC_CLKin2_MUX
          5. 8.6.3.4.5 SYNC_QUAL
          6. 8.6.3.4.6 SYNC_POL_INV
          7. 8.6.3.4.7 SYNC_EN_AUTO
          8. 8.6.3.4.8 SYNC_TYPE
          9. 8.6.3.4.9 EN_PLL2_XTAL
        5. 8.6.3.5  Register R12
          1. 8.6.3.5.1 LD_MUX
          2. 8.6.3.5.2 LD_TYPE
          3. 8.6.3.5.3 SYNC_PLLX_DLD
          4. 8.6.3.5.4 EN_TRACK
          5. 8.6.3.5.5 HOLDOVER_MODE
        6. 8.6.3.6  Register R13
          1. 8.6.3.6.1 HOLDOVER_MUX
          2. 8.6.3.6.2 HOLDOVER_TYPE
          3. 8.6.3.6.3 Status_CLKin1_MUX
          4. 8.6.3.6.4 Status_CLKin0_TYPE
          5. 8.6.3.6.5 DISABLE_DLD1_DET
          6. 8.6.3.6.6 Status_CLKin0_MUX
          7. 8.6.3.6.7 CLKin_SELECT_MODE
          8. 8.6.3.6.8 CLKin_Sel_INV
          9. 8.6.3.6.9 EN_CLKinX
        7. 8.6.3.7  Register 14
          1. 8.6.3.7.1 LOS_TIMEOUT
          2. 8.6.3.7.2 EN_LOS
          3. 8.6.3.7.3 Status_CLKin1_TYPE
          4. 8.6.3.7.4 CLKinX_BUF_TYPE, PLL1 CLKinX/CLKinX* Buffer Type
          5. 8.6.3.7.5 DAC_HIGH_TRIP
          6. 8.6.3.7.6 DAC_LOW_TRIP
          7. 8.6.3.7.7 EN_VTUNE_RAIL_DET
        8. 8.6.3.8  Register 15
          1. 8.6.3.8.1 MAN_DAC
          2. 8.6.3.8.2 EN_MAN_DAC
          3. 8.6.3.8.3 HOLDOVER_DLD_CNT
          4. 8.6.3.8.4 FORCE_HOLDOVER
        9. 8.6.3.9  Register 16
          1. 8.6.3.9.1 XTAL_LVL
        10. 8.6.3.10 Register 23
          1. 8.6.3.10.1 DAC_CNT
        11. 8.6.3.11 REGISTER 24
          1. 8.6.3.11.1 PLL2_C4_LF, PLL2 Integrated Loop Filter Component
          2. 8.6.3.11.2 PLL2_C3_LF, PLL2 Integrated Loop Filter Component
          3. 8.6.3.11.3 PLL2_R4_LF, PLL2 Integrated Loop Filter Component
          4. 8.6.3.11.4 PLL2_R3_LF, PLL2 Integrated Loop Filter Component
          5. 8.6.3.11.5 PLL1_N_DLY
          6. 8.6.3.11.6 PLL1_R_DLY
          7. 8.6.3.11.7 PLL1_WND_SIZE
        12. 8.6.3.12 Register 25
          1. 8.6.3.12.1 DAC_CLK_DIV
          2. 8.6.3.12.2 PLL1_DLD_CNT
        13. 8.6.3.13 Register 26
          1. 8.6.3.13.1 PLL2_WND_SIZE
          2. 8.6.3.13.2 EN_PLL2_REF_2X, PLL2 Reference Frequency Doubler
          3. 8.6.3.13.3 PLL2_CP_POL, PLL2 Charge Pump Polarity
          4. 8.6.3.13.4 PLL2_CP_GAIN, PLL2 Charge Pump Current
          5. 8.6.3.13.5 PLL2_DLD_CNT
          6. 8.6.3.13.6 PLL2_CP_TRI, PLL2 Charge Pump Tri-State
        14. 8.6.3.14 Register 27
          1. 8.6.3.14.1 PLL1_CP_POL, PLL1 Charge Pump Polarity
          2. 8.6.3.14.2 PLL1_CP_GAIN, PLL1 Charge Pump Current
          3. 8.6.3.14.3 CLKinX_PreR_DIV
          4. 8.6.3.14.4 PLL1_R, PLL1 R Divider
          5. 8.6.3.14.5 PLL1_CP_TRI, PLL1 Charge Pump Tri-State
        15. 8.6.3.15 Register 28
          1. 8.6.3.15.1 PLL2_R, PLL2 R Divider
          2. 8.6.3.15.2 PLL1_N, PLL1 N Divider
        16. 8.6.3.16 Register 29
          1. 8.6.3.16.1 OSCin_FREQ, PLL2 Oscillator Input Frequency Register
          2. 8.6.3.16.2 PLL2_FAST_PDF, High PLL2 Phase Detector Frequency
          3. 8.6.3.16.3 PLL2_N_CAL, PLL2 N Calibration Divider
        17. 8.6.3.17 Register 30
          1. 8.6.3.17.1 PLL2_P, PLL2 N Prescaler Divider
          2. 8.6.3.17.2 PLL2_N, PLL2 N Divider
        18. 8.6.3.18 Register 31
          1. 8.6.3.18.1 READBACK_LE
          2. 8.6.3.18.2 READBACK_ADDR
          3. 8.6.3.18.3 uWire_LOCK
  9. Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Loop Filter
        1. 9.1.1.1 PLL1
        2. 9.1.1.2 PLL2
      2. 9.1.2 Driving CLKin and OSCin Inputs
        1. 9.1.2.1 Driving CLKin Pins With a Differential Source
        2. 9.1.2.2 Driving CLKin Pins With a Single-Ended Source
      3. 9.1.3 Termination and Use of Clock Output (Drivers)
        1. 9.1.3.1 Termination for DC-Coupled Differential Operation
        2. 9.1.3.2 Termination for AC-Coupled Differential Operation
        3. 9.1.3.3 Termination for Single-Ended Operation
      4. 9.1.4 Frequency Planning With the LMK04816
      5. 9.1.5 PLL Programming
        1. 9.1.5.1 Example PLL2 N Divider Programming
      6. 9.1.6 Digital Lock Detect Frequency Accuracy
        1. 9.1.6.1 Minimum Lock Time Calculation Example
      7. 9.1.7 Calculating Dynamic Digital Delay Values for Any Divide
        1. 9.1.7.1 Example
      8. 9.1.8 Optional Crystal Oscillator Implementation (OSCin and OSCin*)
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Device Selection
          1. 9.2.2.1.1 Clock Architect
          2. 9.2.2.1.2 Clock Design Tool
          3. 9.2.2.1.3 Calculation Using LCM
        2. 9.2.2.2 Device Configuration
          1. 9.2.2.2.1 PLL LO Reference
          2. 9.2.2.2.2 POR Clock
        3. 9.2.2.3 PLL Loop Filter Design
          1. 9.2.2.3.1 PLL1 Loop Filter Design
          2. 9.2.2.3.2 PLL2 Loop Filter Design
        4. 9.2.2.4 Clock Output Assignment
        5. 9.2.2.5 Other Device Specific Configuration
          1. 9.2.2.5.1 Digital Lock Detect
          2. 9.2.2.5.2 Holdover
        6. 9.2.2.6 Device Programming
      3. 9.2.3 Application Curve
    3. 9.3 System Examples
  10. 10Power Supply Recommendations
    1. 10.1 Pin Connection Recommendations
      1. 10.1.1 Vcc Pins and Decoupling
        1. 10.1.1.1 Vcc2, Vcc3, Vcc10, Vcc11, Vcc12, Vcc13 (CLKout Vccs)
        2. 10.1.1.2 Vcc1 (VCO), Vcc4 (Digital), and Vcc9 (PLL2)
        3. 10.1.1.3 Vcc6 (PLL1 Charge Pump) and Vcc8 (PLL2 Charge Pump)
        4. 10.1.1.4 Vcc5 (CLKin), Vcc7 (OSCin and OSCout0)
      2. 10.1.2 LVPECL Outputs
      3. 10.1.3 Unused Clock Outputs
      4. 10.1.4 Unused Clock Inputs
      5. 10.1.5 LDO Bypass
    2. 10.2 Current Consumption and Power Dissipation Calculations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Development Support
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Community Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

パッケージ・オプション

メカニカル・データ(パッケージ|ピン)
サーマルパッド・メカニカル・データ
発注情報

11 Layout

11.1 Layout Guidelines

Power consumption of the LMK04816 can be high enough to require attention to thermal management. For reliability and performance reasons the die temperature must be limited to a maximum of 125°C. That is, as an estimate, TA (ambient temperature) plus device power consumption times RθJA must not exceed 125°C.

The package of the device has an exposed pad that provides the primary heat removal path as well as excellent electrical grounding to a printed-circuit-board. To maximize the removal of heat from the package a thermal land pattern including multiple vias to a ground plane must be incorporated on the PCB within the footprint of the package. The exposed pad must be soldered down to ensure adequate heat conduction out of the package.

A recommended land and via pattern is shown in Figure 43. More information on soldering WQFN, previously referred to as LLP packages, see Absolute Maximum Ratings for Soldering (SNOA549).

To minimize junction temperature, TI recommends that a simple heat sink be built into the PCB (if the ground plane layer is not exposed). This is done by including a copper area on the opposite side of the PCB from the device. This copper area may be plated or solder coated to prevent corrosion, but must not have conformal coating (if possible), which could provide thermal insulation. The vias shown in Figure 43 must connect these top and bottom copper layers and to the ground layer. These vias act as heat pipes to carry the thermal energy away from the device side of the board to where it can be more effectively dissipated. Avoid routing traces close to exposed ground pad to ensure proper thermal flow on the PCB.

LMK04816 30102373.gif Figure 43. Recommended Land and Via Pattern

11.2 Layout Example

LMK04816 layout_snas645.gif Figure 44. LMK04816 Layout Example