SCAS918E June   2013  – August 2024 CDCE913-Q1 , CDCEL913-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison
  6. 5 Pin Configuration and Functions
  7. 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 Requirements
    7. 6.7 Typical Characteristics
  8. 7 Parameter Measurement Information
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Control Terminal Configuration
      2. 8.3.2 Default Device Configuration
      3. 8.3.3 I2C Serial Interface
      4. 8.3.4 Data Protocol
    4. 8.4 Device Functional Modes
      1. 8.4.1 SDA and SCL Hardware Interface
    5. 8.5 Programming
  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. 10Register Maps
    1. 10.1 I2C Configuration Registers
  12. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  13. 12Revision History
  14. 13Mechanical, Packaging, and Orderable Information

Package Options

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

9.2.1 Design Requirements

The CDCE913-Q1 device supports spread-spectrum clocking (SSC) with multiple control parameters:

  • Modulation amount (%)
  • Modulation frequency (>20 kHz)
  • Modulation shape (triangular, Hershey, and others)
  • Center spread or down spread (± or –)

Consider the following sample design requirements:

  • EMI ≤ 55 dBmV
  • CLK1 frequency = 27 MHz
  • CLK2 frequency = 54 MHz
  • CLK3 frequency = 108 MHz

For sample calculations of PLL constants, see PLL Frequency Planning.

CDCE913-Q1 CDCEL913-Q1 Modulation Frequency (fm) and Modulation AmountFigure 9-2 Modulation Frequency (fm) and Modulation Amount
CDCE913-Q1 CDCEL913-Q1 Spread Spectrum Modulation ShapesFigure 9-3 Spread Spectrum Modulation Shapes