SLAS564I August   2007  – December 2024 CDCE937 , CDCEL937

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: CLK_IN
    7. 5.7 Timing Requirements: SDA/SCL
    8. 5.8 EEPROM Specification
    9. 5.9 Typical Characteristics
  7. 6 Parameter Measurement Information
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Control Terminal Setting
      2. 7.3.2 Default Device Setting
      3. 7.3.3 SDA/SCL Serial Interface
      4. 7.3.4 Data Protocol
    4. 7.4 Device Functional Modes
      1. 7.4.1 SDA/SCL Hardware Interface
    5. 7.5 Programming
  9. 8 Register Maps
    1. 8.1 SDA/SCL Configuration Registers
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Spread Spectrum Clock (SSC)
        2. 9.2.2.2 PLL Frequency Planning
        3. 9.2.2.3 Crystal Oscillator Start-Up
        4. 9.2.2.4 Frequency Adjustment With Crystal Oscillator Pulling
        5. 9.2.2.5 Unused Inputs and Outputs
        6. 9.2.2.6 Switching Between XO and VCXO Mode
      3. 9.2.3 Application Curves
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Device Support
      1. 10.1.1 Third-Party Products Disclaimer
      2. 10.1.2 Development Support
    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 Electrostatic Discharge Caution
    7. 10.7 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

9.3 Power Supply Recommendations

When using an external reference clock, Xin/CLK must be driven before VDD ramps to avoid risk of unstable output. If VDDOUT is applied before VDD, TI recommends keeping VDD pulled to GND until VDDOUT is ramped. In case the VDDOUT is powered while VDD is floating, there is a risk of high current flowing on the VDDOUT.

The device has a power-up control that is connected to the 1.8V supply. This keeps the whole device disabled until the 1.8V supply reaches a sufficient voltage level. Then the device switches on all internal components, including the outputs. If there is a 3.3V Vddout available before the 1.8V, the outputs remain disabled until the 1.8V supply has reached a certain level.