JAJSRL8I June   2007  – August 2024 CDCE913 , CDCEL913

PRODUCTION DATA  

  1.   1
  2. 1 特長
  3. 2 アプリケーション
  4. 3 概要
  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 EEPROM Specification
    7. 5.7 Timing Requirements: CLK_IN
    8. 5.8 Timing Requirements: SDA/SCL #GUID-DE171716-D3A0-4375-A25C-58C636304087/SCAS849414
    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 Configuration
      2. 7.3.2 Default Device Configuration
      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 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Spread-Spectrum Clock (SSC)
        2. 8.2.2.2 PLL Frequency Planning
        3. 8.2.2.3 Crystal Oscillator Start-up
        4. 8.2.2.4 Frequency Adjustment with Crystal Oscillator Pulling
        5. 8.2.2.5 Unused Inputs/Outputs
        6. 8.2.2.6 Switching Between XO and VCXO Mode
      3. 8.2.3 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. 9 Register Maps
    1. 9.1 SDA/SCL Configuration Registers
  11. 10Device and Documentation Support
    1. 10.1 Documentation Support
      1. 10.1.1 Related Documentation
    2. 10.2 ドキュメントの更新通知を受け取る方法
    3. 10.3 サポート・リソース
    4. 10.4 Trademarks
    5. 10.5 静電気放電に関する注意事項
    6. 10.6 用語集
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

8.2.2.1 Spread-Spectrum Clock (SSC)

Spread-spectrum modulation is a method to spread emitted energy over a larger bandwidth. In clocking, spread spectrum can reduce Electromagnetic Interference (EMI) by reducing the level of emission from clock distribution network.

CDCE913 CDCEL913 Comparison Between Typical Clock Power Spectrum and Spread-Spectrum Clock
CDCS502 with a 25-MHz Crystal, FS = 1, Fout = 100 MHz, and 0%, ±0.5, ±1%, and ±2% SSC
Figure 8-4 Comparison Between Typical Clock Power Spectrum and Spread-Spectrum Clock