SNAS750B November   2020  – March 2021 LMK5C33216

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Timing Diagrams
  8. 8 Parameter Measurement Information
    1. 8.1 Differential Voltage Measurement Terminology
    2. 8.2 Output Clock Test Configurations
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
      1. 9.2.1 PLL Architecture Overview
      2. 9.2.2 DPLL
        1. 9.2.2.1 Independent DPLL Operation
        2. 9.2.2.2 Cascaded DPLL Operation
        3. 9.2.2.3 APLL Cascaded with DPLL
      3. 9.2.3 APLL-Only Mode
    3. 9.3 Feature Description
      1. 9.3.1  Oscillator Input (XO)
      2. 9.3.2  Reference Inputs
      3. 9.3.3  Clock Input Interfacing and Termination
      4. 9.3.4  Reference Input Mux Selection
        1. 9.3.4.1 Automatic Input Selection
        2. 9.3.4.2 Manual Input Selection
      5. 9.3.5  Hitless Switching
        1. 9.3.5.1 Hitless Switching with Phase Cancellation
        2. 9.3.5.2 Hitless Switching With Phase Slew Control
        3. 9.3.5.3 Hitless Switching With 1-PPS Inputs
      6. 9.3.6  Gapped Clock Support on Reference Inputs
      7. 9.3.7  Input Clock and PLL Monitoring, Status, and Interrupts
        1. 9.3.7.1 XO Input Monitoring
        2. 9.3.7.2 Reference Input Monitoring
          1. 9.3.7.2.1 Reference Validation Timer
          2. 9.3.7.2.2 Frequency Monitoring
          3. 9.3.7.2.3 Missing Pulse Monitor (Late Detect)
          4. 9.3.7.2.4 Runt Pulse Monitor (Early Detect)
          5. 9.3.7.2.5 Phase Valid Monitor for 1-PPS Inputs
        3. 9.3.7.3 PLL Lock Detectors
        4. 9.3.7.4 Tuning Word History
        5. 9.3.7.5 Status Outputs
        6. 9.3.7.6 Interrupt
      8. 9.3.8  PLL Relationships
        1. 9.3.8.1  PLL Frequency Relationships
          1. 9.3.8.1.1 APLL Phase Detector Frequency
          2. 9.3.8.1.2 APLL VCO Frequency
          3. 9.3.8.1.3 DPLL TDC Frequency
          4. 9.3.8.1.4 DPLL VCO Frequency
          5. 9.3.8.1.5 Clock Output Frequency
        2. 9.3.8.2  Analog PLLs (APLL1, APLL2, APLL3)
        3. 9.3.8.3  APLL Reference Paths
          1. 9.3.8.3.1 APLL XO Doubler
          2. 9.3.8.3.2 APLL XO Reference (R) Divider
        4. 9.3.8.4  APLL Phase Frequency Detector (PFD) and Charge Pump
        5. 9.3.8.5  APLL Feedback Divider Paths
          1. 9.3.8.5.1 APLL N Divider with SDM
        6. 9.3.8.6  APLL Loop Filters (LF1, LF2, LF3)
        7. 9.3.8.7  APLL Voltage Controlled Oscillators (VCO1, VCO2, VCO3)
          1. 9.3.8.7.1 VCO Calibration
        8. 9.3.8.8  APLL VCO Clock Distribution Paths
        9. 9.3.8.9  DPLL Reference (R) Divider Paths
        10. 9.3.8.10 DPLL Time-to-Digital Converter (TDC)
        11. 9.3.8.11 DPLL Loop Filter (DLF)
        12. 9.3.8.12 DPLL Feedback (FB) Divider Path
      9. 9.3.9  Output Clock Distribution
      10. 9.3.10 Output Channel Muxes
      11. 9.3.11 Output Dividers (OD)
      12. 9.3.12 SYSREF
      13. 9.3.13 Output Delay
      14. 9.3.14 Clock Outputs (OUTx_P/N)
        1. 9.3.14.1 Differential Output
        2. 9.3.14.2 LVCMOS Output
        3. 9.3.14.3 Output Auto-Mute During LOL
      15. 9.3.15 Glitchless Output Clock Start-Up
      16. 9.3.16 Clock Output Interfacing and Termination
      17. 9.3.17 Output Synchronization (SYNC)
      18. 9.3.18 Zero-Delay Mode (ZDM) Synchronization
      19. 9.3.19 Time of Day (ToD) Counter
        1. 9.3.19.1 Configuring ToD Functionality
        2. 9.3.19.2 SPI as a Trigger Source
        3. 9.3.19.3 GPIO Pin as a ToD Trigger Source
          1. 9.3.19.3.1 An Example: Making a time measurement using ToD and GPIO1 as trigger
        4. 9.3.19.4 ToD Timing
        5. 9.3.19.5 Other ToD Behavior
    4. 9.4 Device Functional Modes
      1. 9.4.1 Device Start-Up
        1. 9.4.1.1 ROM Selection
        2. 9.4.1.2 EEPROM Overlay
      2. 9.4.2 DPLL Operating States
        1. 9.4.2.1 Free-Run
        2. 9.4.2.2 Lock Acquisition
        3. 9.4.2.3 DPLL Locked
        4. 9.4.2.4 Holdover
      3. 9.4.3 PLL Start-Up Sequence
      4. 9.4.4 Digitally-Controlled Oscillator (DCO) Frequency and Phase Adjustment
        1. 9.4.4.1 DPLL DCO Control
          1. 9.4.4.1.1 DPLL DCO Relative Adjustment Frequency Step Size
          2. 9.4.4.1.2 APLL DCO Frequency Step Size
      5. 9.4.5 APLL Frequency Control
      6. 9.4.6 Zero-Delay Mode Synchronization
    5. 9.5 Programming
      1. 9.5.1 Interface and Control
      2. 9.5.2 I2C Serial Interface
        1. 9.5.2.1 I2C Block Register Transfers
      3. 9.5.3 SPI Serial Interface
        1. 9.5.3.1 SPI Block Register Transfer
      4. 9.5.4 Register Map Generation
      5. 9.5.5 General Register Programming Sequence
  10. 10Application and Implementation
    1. 10.1 Application Information
      1. 10.1.1 Device Start-Up Sequence
      2. 10.1.2 Power Down (PD#) Pin
      3. 10.1.3 Strap Pins for Start-Up
      4. 10.1.4 ROM and EEPROM
      5. 10.1.5 Power Rail Sequencing, Power Supply Ramp Rate, and Mixing Supply Domains
        1. 10.1.5.1 Power-On Reset (POR) Circuit
        2. 10.1.5.2 Powering Up From a Single-Supply Rail
        3. 10.1.5.3 Power Up From Split-Supply Rails
        4. 10.1.5.4 Non-Monotonic or Slow Power-Up Supply Ramp
      6. 10.1.6 Slow or Delayed XO Start-Up
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
    3. 10.3 Do's and Don'ts
  11. 11Power Supply Recommendations
    1. 11.1 Power Supply Bypassing
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
    3. 12.3 Thermal Reliability
      1. 12.3.1 Support for PCB Temperature up to 105°C
  13. 13Device and Documentation Support
    1. 13.1 Documentation Support
      1. 13.1.1 Related Documentation
    2. 13.2 Receiving Notification of Documentation Updates
    3. 13.3 Support Resources
    4. 13.4 Trademarks
    5. 13.5 Glossary
    6. 13.6 Electrostatic Discharge Caution
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

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

9.3.2 Reference Inputs

The reference inputs (IN0 and IN1) can accept differential or single-ended clocks. Each input has programmable input type, termination, and DC-coupled or AC-coupled input biasing configurations as shown in Figure 9-9. Each input buffer drives the reference input mux of the DPLL block. The DPLL input mux can select from any of the reference inputs. The DPLL can switch between inputs with different frequencies provided they can be divided-down to a common frequency by DPLL R dividers. The reference input paths also drive the various detector blocks for reference input monitoring and validation. DC-path switch can bypass internal AC-coupling capacitors to make low frequency input work robustly.

GUID-20201023-CA0I-6BJQ-N154-XV4B5XQBXW1V-low.svgFigure 9-9 Reference Input Buffer

Table 9-2 lists the reference input buffer configurations for common clock interface types.

Table 9-2 Reference Input Buffer Modes
REFx_DC_COUPLED_EN, REFx_TYPE INPUT TYPES INTERNAL SWITCH SETTINGS
INTERNAL SINGLE-END TERM. (S1)(2) INTERNAL DIFFERENTIAL TERM. (S2) (2) INTERNAL BIAS (S3)(3) LVCMOS/DIFF INTERNAL AC CAPACITOR BYPASS MODE (S4)(1)
0x00, 0x00 DC-Differential (external termination) OFF OFF OFF OFF
0x00, 0x01 AC-Differential (external termination) OFF OFF ON (1.3 V) OFF
0x00, 0x02 DC-Differential (internal termination) OFF 100 Ω OFF OFF
0x00, 0x03 LVDS / HSDS, AC-Differential (internal termination) OFF 100 Ω ON (1.3 V) OFF
0x00, 0x04 HCSL,DC-Differential (internal termination 50-Ω) 50 Ω OFF OFF OFF
0x00, 0x05 LVPECL,AC-Differential (internal termination 50-Ω) 50 Ω OFF ON (1.3 V) OFF
0x00, 0x08 LVCMOS(External DC-coupling, internal AC coupling) OFF OFF OFF OFF
0x01, 0x08 LVCMOS (External DC-coupling, internal DC coupling) OFF OFF OFF ON
0x01, 0x0C LVCMOS(External DC-coupling, internal DC coupling, internal termination 50-Ω) 50 Ω OFF OFF ON
(1) S4: OFF = Differential input amplitude detector is used for all input types except LVCMOS or Single-ended.
(2) S1, S2: OFF = External termination is assumed.
(3) S3: OFF = External input bias or DC coupling is assumed.