SNAS851 December   2023 LMX1906-SP

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 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 Requirements
    7. 5.7 Timing Diagram
    8. 5.8 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
      1. 6.1.1 Range of Dividers and Multiplier
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Power On Reset
      2. 6.3.2 Temperature Sensor
      3. 6.3.3 Clock Outputs
        1. 6.3.3.1 Clock Output Buffers
        2. 6.3.3.2 Clock MUX
        3. 6.3.3.3 Clock Divider
        4. 6.3.3.4 Clock Multiplier
          1. 6.3.3.4.1 General Information about the Clock Multiplier
          2. 6.3.3.4.2 State Machine Clock for the Clock Multiplier
            1. 6.3.3.4.2.1 State Machine Clock
          3. 6.3.3.4.3 Calibration for the Clock Multiplier
          4. 6.3.3.4.4 Lock Detect for the Clock Multiplier
          5. 6.3.3.4.5 Watchdog Timer
      4. 6.3.4 Device Functional Modes Configurations
      5. 6.3.5 LOGICLK Output
        1. 6.3.5.1 LOGICLK Output Format
        2. 6.3.5.2 LOGICLK_DIV_PRE and LOGICLK_DIV Dividers
      6. 6.3.6 SYSREF
        1. 6.3.6.1 SYSREF Output Buffers
          1. 6.3.6.1.1 SYSREF Output Buffers for Main Clocks (SYSREFOUT)
          2. 6.3.6.1.2 SYSREF Output Buffer for LOGICLK
        2. 6.3.6.2 SYSREF Frequency and Delay Generation
        3. 6.3.6.3 SYSREFREQ pins and SYSREFREQ_FORCE Field
          1. 6.3.6.3.1 SYSREFREQ Pins Common-Mode Voltage
          2. 6.3.6.3.2 SYSREFREQ Windowing Feature
            1. 6.3.6.3.2.1 General Procedure Flowchart for SYSREF Windowing Operation
            2. 6.3.6.3.2.2 SYSREFREQ Repeater Mode With Delay Gen (Retime)
            3. 6.3.6.3.2.3 Other Pointers With SYSREF Windowing
            4. 6.3.6.3.2.4 For Glitch-Free Output
            5. 6.3.6.3.2.5 If Using SYNC Feature
          3. 6.3.6.3.3 SYNC Feature
      7. 6.3.7 Pin Mode Control
        1. 6.3.7.1 Chip Enable (CE)
        2. 6.3.7.2 Output Channel Control
        3. 6.3.7.3 Logic Output Control
        4. 6.3.7.4 SYSREF Output Control
        5. 6.3.7.5 Device Mode Selection
        6. 6.3.7.6 Divider or Multiplier Value Selection
        7. 6.3.7.7 Calibration Control Pin
        8. 6.3.7.8 Output Power Control
  8. 7 Application and Implementation
    1. 7.1 Applications Information
      1. 7.1.1 SYSREFREQ Input Configuration
      2. 7.1.2 Treatment of Unused Pins
      3. 7.1.3 Current Consumption
    2. 7.2 Typical Applications
      1. 7.2.1 Local Oscillator Distribution Application
        1. 7.2.1.1 Design Requirements
        2. 7.2.1.2 Detailed Design Procedure
        3. 7.2.1.3 Application Plots
      2. 7.2.2 JESD204B/C Clock Distribution Application
    3. 7.3 Power Supply Recommendations
      1. 7.3.1 Power-Up Timing
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
    5. 7.5 Register Map
      1. 7.5.1 Device Registers
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
    2. 8.2 Receiving Notification of Documentation Updates
    3. 8.3 Support Resources
    4. 8.4 Trademarks
    5. 8.5 Electrostatic Discharge Caution
    6. 8.6 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

Package Options

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

7.3 Power Supply Recommendations

This devices uses a 2.5-V supply for the whole device. A direct connection to a switching power supply will likely result in unwanted spurs at the output. Bypassing can be done individually at all the power pins. TI recommends placing smaller capacitors with higher frequency of minimum impedance on the same layer as the device, as close to the pins as possible. Since the frequencies of nearly all signals in the device are 100 MHz or greater, therefore larger value bypass capacitors with low frequency of minimum impedance are only used for internal LDO stability, and their distance to the device (and the loop inductance of the bypass path) can be larger. Isolate the supply pins for the clocks and the LOGICLK with a small resistor or ferrite bead if both are being used simultaneously. See the Pin Configuration and Functions section for additional recommendations for each pin.

Note: This device has minimal PSRR due to the low operating voltage and internal filtering by LDOs. It is important that this device is connected to a low noise supply that does not have excessive spurious noise.