SNAS835 September   2022 LMK5B33414

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and 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
    6. 6.6 Timing Diagrams
    7. 6.7 Typical Characteristics
  7. 7 Parameter Measurement Information
    1. 7.1 Differential Voltage Measurement Terminology
    2. 7.2 Output Clock Test Configurations
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
      1. 8.2.1 PLL Architecture Overview
      2. 8.2.2 DPLL
        1. 8.2.2.1 Independent DPLL Operation
        2. 8.2.2.2 Cascaded DPLL Operation
        3. 8.2.2.3 APLL Cascaded With DPLL
      3. 8.2.3 APLL-Only Mode
    3. 8.3 Feature Description
      1. 8.3.1  Oscillator Input (XO)
      2. 8.3.2  Reference Inputs
      3. 8.3.3  Clock Input Interfacing and Termination
      4. 8.3.4  Reference Input Mux Selection
        1. 8.3.4.1 Automatic Input Selection
        2. 8.3.4.2 Manual Input Selection
      5. 8.3.5  Hitless Switching
        1. 8.3.5.1 Hitless Switching With Phase Cancellation
        2. 8.3.5.2 Hitless Switching With Phase Slew Control
        3. 8.3.5.3 Hitless Switching With 1-PPS Inputs
      6. 8.3.6  Gapped Clock Support on Reference Inputs
      7. 8.3.7  Input Clock and PLL Monitoring, Status, and Interrupts
        1. 8.3.7.1 XO Input Monitoring
        2. 8.3.7.2 Reference Input Monitoring
          1. 8.3.7.2.1 Reference Validation Timer
          2. 8.3.7.2.2 Frequency Monitoring
          3. 8.3.7.2.3 Missing Pulse Monitor (Late Detect)
          4. 8.3.7.2.4 Runt Pulse Monitor (Early Detect)
          5. 8.3.7.2.5 Phase Valid Monitor for 1-PPS Inputs
        3. 8.3.7.3 PLL Lock Detectors
        4. 8.3.7.4 Tuning Word History
        5. 8.3.7.5 Status Outputs
        6. 8.3.7.6 Interrupt
      8. 8.3.8  PLL Relationships
        1. 8.3.8.1  PLL Frequency Relationships
          1. 8.3.8.1.1 APLL Phase Detector Frequency
          2. 8.3.8.1.2 APLL VCO Frequency
          3. 8.3.8.1.3 DPLL TDC Frequency
          4. 8.3.8.1.4 DPLL VCO Frequency
          5. 8.3.8.1.5 Clock Output Frequency
        2. 8.3.8.2  Analog PLLs (APLL1, APLL2, APLL3)
        3. 8.3.8.3  APLL Reference Paths
          1. 8.3.8.3.1 APLL XO Doubler
          2. 8.3.8.3.2 APLL XO Reference (R) Divider
        4. 8.3.8.4  APLL Phase Frequency Detector (PFD) and Charge Pump
        5. 8.3.8.5  APLL Feedback Divider Paths
          1. 8.3.8.5.1 APLL N Divider With SDM
        6. 8.3.8.6  APLL Loop Filters (LF1, LF2, LF3)
        7. 8.3.8.7  APLL Voltage-Controlled Oscillators (VCO1, VCO2, VCO3)
          1. 8.3.8.7.1 VCO Calibration
        8. 8.3.8.8  APLL VCO Clock Distribution Paths
        9. 8.3.8.9  DPLL Reference (R) Divider Paths
        10. 8.3.8.10 DPLL Time-to-Digital Converter (TDC)
        11. 8.3.8.11 DPLL Loop Filter (DLF)
        12. 8.3.8.12 DPLL Feedback (FB) Divider Path
      9. 8.3.9  Output Clock Distribution
      10. 8.3.10 Output Channel Muxes
      11. 8.3.11 Output Dividers (OD)
      12. 8.3.12 SYSREF/1-PPS
      13. 8.3.13 Output Delay
      14. 8.3.14 Clock Outputs (OUTx_P/N)
        1. 8.3.14.1 Differential Output
        2. 8.3.14.2 LVCMOS Output
        3. 8.3.14.3 SYSREF/1-PPS Output Replication
        4. 8.3.14.4 Output Auto-Mute During LOL
      15. 8.3.15 Glitchless Output Clock Start-Up
      16. 8.3.16 Clock Output Interfacing and Termination
      17. 8.3.17 Output Synchronization (SYNC)
      18. 8.3.18 Zero-Delay Mode (ZDM)
      19. 8.3.19 Time Elapsed Counter (TEC)
        1. 8.3.19.1 Configuring TEC Functionality
        2. 8.3.19.2 SPI as a Trigger Source
        3. 8.3.19.3 GPIO Pin as a TEC Trigger Source
          1. 8.3.19.3.1 An Example: Making a Time Elapsed Measurement Using TEC and GPIO1 as Trigger
        4. 8.3.19.4 TEC Timing
        5. 8.3.19.5 Other TEC Behavior
    4. 8.4 Device Functional Modes
      1. 8.4.1 Device Start-Up
        1. 8.4.1.1 ROM Selection
        2. 8.4.1.2 EEPROM Overlay
      2. 8.4.2 DPLL Operating States
        1. 8.4.2.1 Free-Run
        2. 8.4.2.2 Lock Acquisition
        3. 8.4.2.3 DPLL Locked
        4. 8.4.2.4 Holdover
      3. 8.4.3 PLL Start-Up Sequence
      4. 8.4.4 Digitally-Controlled Oscillator (DCO) Frequency and Phase Adjustment
        1. 8.4.4.1 DPLL DCO Control
          1. 8.4.4.1.1 DPLL DCO Relative Adjustment Frequency Step Size
          2. 8.4.4.1.2 APLL DCO Frequency Step Size
      5. 8.4.5 APLL Frequency Control
      6. 8.4.6 Zero-Delay Mode Synchronization
      7. 8.4.7 DPLL Programmable Phase Delay
    5. 8.5 Programming
      1. 8.5.1 Interface and Control
      2. 8.5.2 I2C Serial Interface
        1. 8.5.2.1 I2C Block Register Transfers
      3. 8.5.3 SPI Serial Interface
        1. 8.5.3.1 SPI Block Register Transfer
      4. 8.5.4 Register Map Generation
      5. 8.5.5 General Register Programming Sequence
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Device Start-Up Sequence
      2. 9.1.2 Power Down (PD#) Pin
      3. 9.1.3 Strap Pins for Start-Up
      4. 9.1.4 Pin States
      5. 9.1.5 ROM and EEPROM
      6. 9.1.6 Power Rail Sequencing, Power Supply Ramp Rate, and Mixing Supply Domains
        1. 9.1.6.1 Power-On Reset (POR) Circuit
        2. 9.1.6.2 Powering Up From a Single-Supply Rail
        3. 9.1.6.3 Power Up From Split-Supply Rails
        4. 9.1.6.4 Non-Monotonic or Slow Power-Up Supply Ramp
      7. 9.1.7 Slow or Delayed XO Start-Up
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curves
    3. 9.3 Do's and Don'ts
    4. 9.4 Power Supply Recommendations
      1. 9.4.1 Power Supply Bypassing
    5. 9.5 Layout
      1. 9.5.1 Layout Guidelines
      2. 9.5.2 Layout Example
      3. 9.5.3 Thermal Reliability
  10. 10Device and Documentation Support
    1. 10.1 Device Support
      1. 10.1.1 Development Support
        1. 10.1.1.1 Clock Tree Architect Programming Software
        2. 10.1.1.2 Texas Instruments Clocks and Synthesizers (TICS) Pro Software
        3. 10.1.1.3 PLLatinum™ Simulation Tool
    2. 10.2 Documentation Support
      1. 10.2.1 Related Documentation
    3. 10.3 Receiving Notification of Documentation Updates
    4. 10.4 Support Resources
    5. 10.5 Trademarks
    6. 10.6 Glossary
    7. 10.7 Electrostatic Discharge Caution
  11. 11Mechanical, Packaging, and Orderable Information

Package Options

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

The precision frequency detector measures the frequency offset or error (in ppm) of all input clocks relative to the XO input's frequency, which is considered as the 0-ppm reference clock for frequency comparison. The valid and invalid ppm frequency thresholds are configurable through the registers. The monitor will clear the REFx_FDET_STATUS flag when the relative input frequency error is less than the valid ppm threshold. Otherwise, the monitor will set the REFx_FDET_STATUS flag when the relative input frequency error is greater than the invalid ppm threshold. The ppm delta between the valid and invalid thresholds provides hysteresis to prevent the REFx_FDET_STATUS flag from toggling when the input frequency offset is crossing these thresholds.

A measurement accuracy (ppm) and averaging factor are used in computing the frequency detector register settings. A higher measurement accuracy (smaller ppm) or higher averaging factor will increase the measurement delay to set or clear the flag, which allows more time for the input frequency to settle, and can also provide better measurement resolution for an input with high drift or wander. Note that higher averaging reduces the maximum frequency ppm thresholds that can be configured.