SNAS816B March   2022  – July 2022 LMK5B33216

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/1PPS
      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/1PPS 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) Synchronization
      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
    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

8.3.17 Output Synchronization (SYNC)

Output SYNC can be used to phase-align two or more output clocks with a common rising edge by allowing the output dividers to exit reset on the same PLL output clock cycle. Any output dividers selecting the same PLL output can be synchronized together as a SYNC group by triggering a SYNC event through the hardware pin or software bit.

The following requirements must be met to establish a SYNC group for two or more output channels:

  • Output dividers have their respective sync enable bit set (OUT_x_y_DIV_SYNC_EN = 1)
  • SYSREF dividers have their additional respective sync enable bit set (OUT_x_y_SR_DIV_SYNC_EN = 1), work with above set (OUT_x_y_DIV_SYNC_EN = 1)
  • Output dividers have their output mux selecting the same PLL output
  • The PLL (post-divider) output has its sync enable bit set (for example, PLL1_PRI_DIV_SYNC_EN = 1)
  • SYNC_EN = 1

A SYNC event can be asserted by either a GPIOx pin programmed for SYNC input with GPIOx_MODE = 31 or the SYNC_SW register bit (active high). When SYNC is asserted, the SYNC-enabled dividers are held in reset and clock outputs are low. When SYNC is deasserted, the outputs from a common PLL will start with their initial clock phases synchronized or aligned. SYNC can also be used to set a low state on any SYNC-enabled outputs to prevent output clocks from being distributed to downstream devices until the receiver inputs are configured and ready to accept the incoming clock.

Output channels with their sync disabled (OUT_x_y_DIV_SYNC_EN = 0) will not be affected by a SYNC event and will continue normal output operation as configured. VCO post-divider clocks must be enabled for synchronization to ensure the dividers they drive are synchronized accurately. However, any output deriving a clock from a reset VCO post-divider will not be valid during SYNC, even if the channel divider is not selected for SYNC. VCO post-dividers not selected for synchronization do not stop running during the SYNC so they can continue to source output channels that do not require synchronization. Output dividers with divide-by-1 (divider bypass mode) are not gated during the SYNC event.

Table 8-3 Output Synchronization
GPIOx as SYNC PIN
GPIOx_MODE = 31		SYNC_SW
R21[6]		OUTPUT DIVIDER AND DRIVER STATE
GPIOx_POL = 0GPIOx_POL = 1
101Output driver(s) muted and output divider(s) reset
1 → 00 → 11 → 0SYNCed outputs are released with synchronized phase
010Normal output driver/divider operation as configured