SNAS751 December   2023 LMK5C33414A

PRODUCTION DATA  

  1.   1
  2. Features
  3. Applications
  4. Description
  5. Pin Configuration and Functions
  6. Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Timing Diagrams
    7. 5.7 Typical Characteristics
  7. Parameter Measurement Information
    1. 6.1 Differential Voltage Measurement Terminology
    2. 6.2 Output Clock Test Configurations
  8. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
      1. 7.2.1 PLL Architecture Overview
      2. 7.2.2 DPLL
        1. 7.2.2.1 Independent DPLL Operation
        2. 7.2.2.2 Cascaded DPLL Operation
        3. 7.2.2.3 APLL Cascaded with DPLL
      3. 7.2.3 APLL-Only Mode
    3. 7.3 Feature Description
      1. 7.3.1  Oscillator Input (XO)
      2. 7.3.2  Reference Inputs
      3. 7.3.3  Clock Input Interfacing and Termination
      4. 7.3.4  Reference Input Mux Selection
        1. 7.3.4.1 Automatic Input Selection
        2. 7.3.4.2 Manual Input Selection
      5. 7.3.5  Hitless Switching
        1. 7.3.5.1 Hitless Switching With Phase Cancellation
        2. 7.3.5.2 Hitless Switching With Phase Slew Control
        3. 7.3.5.3 Hitless Switching With 1-PPS Inputs
      6. 7.3.6  Gapped Clock Support on Reference Inputs
      7. 7.3.7  Input Clock and PLL Monitoring, Status, and Interrupts
        1. 7.3.7.1 XO Input Monitoring
        2. 7.3.7.2 Reference Input Monitoring
          1. 7.3.7.2.1 Reference Validation Timer
          2. 7.3.7.2.2 Frequency Monitoring
          3. 7.3.7.2.3 Missing Pulse Monitor (Late Detect)
          4. 7.3.7.2.4 Runt Pulse Monitor (Early Detect)
          5. 7.3.7.2.5 Phase Valid Monitor for 1-PPS Inputs
        3. 7.3.7.3 PLL Lock Detectors
        4. 7.3.7.4 Tuning Word History
        5. 7.3.7.5 Status Outputs
        6. 7.3.7.6 Interrupt
      8. 7.3.8  PLL Relationships
        1. 7.3.8.1  PLL Frequency Relationships
          1. 7.3.8.1.1 APLL Phase Detector Frequency
          2. 7.3.8.1.2 APLL VCO Frequency
          3. 7.3.8.1.3 DPLL TDC Frequency
          4. 7.3.8.1.4 DPLL VCO Frequency
          5. 7.3.8.1.5 Clock Output Frequency
        2. 7.3.8.2  Analog PLLs (APLL1, APLL2, APLL3)
        3. 7.3.8.3  APLL Reference Paths
          1. 7.3.8.3.1 APLL XO Doubler
          2. 7.3.8.3.2 APLL XO Reference (R) Divider
        4. 7.3.8.4  APLL Phase Frequency Detector (PFD) and Charge Pump
        5. 7.3.8.5  APLL Feedback Divider Paths
          1. 7.3.8.5.1 APLL N Divider With SDM
        6. 7.3.8.6  APLL Loop Filters (LF1, LF2, LF3)
        7. 7.3.8.7  APLL Voltage-Controlled Oscillators (VCO1, VCO2, VCO3)
          1. 7.3.8.7.1 VCO Calibration
        8. 7.3.8.8  APLL VCO Clock Distribution Paths
        9. 7.3.8.9  DPLL Reference (R) Divider Paths
        10. 7.3.8.10 DPLL Time-to-Digital Converter (TDC)
        11. 7.3.8.11 DPLL Loop Filter (DLF)
        12. 7.3.8.12 DPLL Feedback (FB) Divider Path
      9. 7.3.9  Output Clock Distribution
      10. 7.3.10 Output Channel Muxes
      11. 7.3.11 Output Dividers (OD)
      12. 7.3.12 SYSREF/1-PPS
      13. 7.3.13 Output Delay
      14. 7.3.14 Clock Outputs (OUTx_P/N)
        1. 7.3.14.1 Differential Output
        2. 7.3.14.2 LVCMOS Output
        3. 7.3.14.3 SYSREF/1-PPS Output Replication
        4. 7.3.14.4 Output Auto-Mute During LOL
      15. 7.3.15 Glitchless Output Clock Start-Up
      16. 7.3.16 Clock Output Interfacing and Termination
      17. 7.3.17 Output Synchronization (SYNC)
      18. 7.3.18 Zero-Delay Mode (ZDM)
      19. 7.3.19 Time Elapsed Counter (TEC)
        1. 7.3.19.1 Configuring TEC Functionality
        2. 7.3.19.2 SPI as a Trigger Source
        3. 7.3.19.3 GPIO Pin as a TEC Trigger Source
          1. 7.3.19.3.1 An Example: Making a Time Elapsed Measurement Using TEC and GPIO1 as Trigger
        4. 7.3.19.4 TEC Timing
        5. 7.3.19.5 Other TEC Behavior
    4. 7.4 Device Functional Modes
      1. 7.4.1 Device Start-Up
        1. 7.4.1.1 ROM Selection
        2. 7.4.1.2 EEPROM Overlay
      2. 7.4.2 DPLL Operating States
        1. 7.4.2.1 Free-Run
        2. 7.4.2.2 Lock Acquisition
        3. 7.4.2.3 DPLL Locked
        4. 7.4.2.4 Holdover
      3. 7.4.3 PLL Start-Up Sequence
      4. 7.4.4 Digitally-Controlled Oscillator (DCO) Frequency and Phase Adjustment
        1. 7.4.4.1 DPLL DCO Control
          1. 7.4.4.1.1 DPLL DCO Relative Adjustment Frequency Step Size
          2. 7.4.4.1.2 APLL DCO Frequency Step Size
      5. 7.4.5 APLL Frequency Control
      6. 7.4.6 DPLL Programmable Phase Delay
    5. 7.5 Programming
      1. 7.5.1 Interface and Control
      2. 7.5.2 I2C Serial Interface
        1. 7.5.2.1 I2C Block Register Transfers
      3. 7.5.3 SPI Serial Interface
        1. 7.5.3.1 SPI Block Register Transfer
      4. 7.5.4 Register Map Generation
      5. 7.5.5 General Register Programming Sequence
  9. Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Device Start-Up Sequence
      2. 8.1.2 Power Down (PD#) Pin
      3. 8.1.3 Strap Pins for Start-Up
      4. 8.1.4 Pin States
      5. 8.1.5 ROM and EEPROM
      6. 8.1.6 Power Rail Sequencing, Power Supply Ramp Rate, and Mixing Supply Domains
        1. 8.1.6.1 Power-On Reset (POR) Circuit
        2. 8.1.6.2 Powering Up From a Single-Supply Rail
        3. 8.1.6.3 Power Up From Split-Supply Rails
        4. 8.1.6.4 Non-Monotonic or Slow Power-Up Supply Ramp
      7. 8.1.7 Slow or Delayed XO Start-Up
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
      3. 8.2.3 Application Curves
    3. 8.3 Best Design Practices
    4. 8.4 Power Supply Recommendations
      1. 8.4.1 Power Supply Bypassing
    5. 8.5 Layout
      1. 8.5.1 Layout Guidelines
      2. 8.5.2 Layout Example
      3. 8.5.3 Thermal Reliability
  10. Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Development Support
        1. 9.1.1.1 Clock Tree Architect Programming Software
        2. 9.1.1.2 Texas Instruments Clocks and Synthesizers (TICS) Pro Software
        3. 9.1.1.3 PLLatinumâ„¢ Simulation Tool
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
    3. 9.3 Receiving Notification of Documentation Updates
    4. 9.4 Support Resources
    5. 9.5 Trademarks
    6. 9.6 Glossary
    7. 9.7 Electrostatic Discharge Caution
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

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

Slow or Delayed XO Start-Up

Because the external XO clock input is used as the reference input for the APLL1/VCO1 and APLL2/VCO2 calibration, the XO input amplitude and frequency must be stable before the start of VCO calibration to ensure successful PLL lock and output start-up. If the XO clock is not stable prior to VCO calibration, the VCO calibration can fail and prevent PLL lock and output clock start-up.

If the XO clock has a slow start-up time or has glitches on power-up (due to a slow or non-monotonic power supply ramp, for example), TI recommends to delay the start of VCO calibration until after the XO is stable. This could be achieved by delaying the PD# low-to-high transition until after the XO clock has stabilized using one of the methods described in Power Up From Split-Supply Rails. It is also possible to issue a device soft-reset after the XO clock has stabilized to manually trigger the VCO calibration and PLL start-up sequence.

APLL3/VCO3 is factory calibrated and is not sensitive to an invalid XO reference start-up. Upon valid XO reference, APLL3/VCO3 will be able to acquire lock. When APLL3/VCO3 is used in conjunction with DPLL3, it is necessary for the XO to be valid before a DPLL3 reference is validated.