ZHCSH72I September   2011  – December 2017 LMK00301

PRODUCTION DATA.  

  1. 特性
  2. 应用
  3. 说明
    1.     Device Images
      1.      功能框图
      2.      LVPECL 输出摆幅 (VOD) 与频率间的关系
  4. 修订历史记录
  5. Device Comparison Table
  6. Pin Configuration and Functions
    1.     Pin Functions
  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 Typical Characteristics
  8. Parameter Measurement Information
    1. 8.1 Differential Voltage Measurement Terminology
  9. Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
      1. 9.2.1 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 VCC and VCCO Power Supplies
      2. 9.3.2 Clock Inputs
      3. 9.3.3 Clock Outputs
        1. 9.3.3.1 Reference Output
  10. 10Application and Implementation
    1. 10.1 Driving the Clock Inputs
    2. 10.2 Crystal Interface
    3. 10.3 Termination and Use of Clock Drivers
      1. 10.3.1 Termination for DC Coupled Differential Operation
      2. 10.3.2 Termination for AC Coupled Differential Operation
      3. 10.3.3 Termination for Single-Ended Operation
  11. 11Power Supply Recommendations
    1. 11.1 Power Supply Sequencing
    2. 11.2 Current Consumption and Power Dissipation Calculations
      1. 11.2.1 Power Dissipation Example #1: Separate Vcc and Vcco Supplies with Unused Outputs
      2. 11.2.2 Power Dissipation Example #2: Worst-Case Dissipation
    3. 11.3 Power Supply Bypassing
      1. 11.3.1 Power Supply Ripple Rejection
    4. 11.4 Thermal Management
  12. 12器件和文档支持
    1. 12.1 文档支持
      1. 12.1.1 相关文档
    2. 12.2 社区资源
    3. 12.3 商标
    4. 12.4 静电放电警告
    5. 12.5 Glossary
  13. 13机械、封装和可订购信息

封装选项

机械数据 (封装 | 引脚)
散热焊盘机械数据 (封装 | 引脚)
订购信息

Termination for Single-Ended Operation

A balun can be used with either LVDS or LVPECL drivers to convert the balanced, differential signal into an unbalanced, single-ended signal.

It is possible to use an LVPECL driver as one or two separate 800 mV p-p signals. When DC coupling one of the LMK00301 LVPECL driver of a CLKoutX/CLKoutX* pair, be sure to properly terminate the unused driver. When DC coupling on of the LMK00301 LVPECL drivers, the termination should be 50 Ω to Vcco - 2 V as shown in Figure 36. The Thevenin equivalent circuit is also a valid termination as shown in Figure 37 for Vcco = 3.3 V.

LMK00301 30147025.gifFigure 36. Single-Ended LVPECL Operation, DC Coupling
LMK00301 30147026.gifFigure 37. Single-Ended LVPECL Operation, DC Coupling, Thevenin Equivalent

When AC coupling an LVPECL driver use a 160 Ω emitter resistor (or 91 Ω for Vcco = 2.5 V) to provide a DC path to ground and ensure a 50 Ω termination with the proper DC bias level for the receiver. The typical DC bias voltage for LVPECL receivers is 2 V. If the companion driver is not used, it should be terminated with either a proper AC or DC termination. This latter example of AC coupling a single-ended LVPECL signal can be used to measure single-ended LVPECL performance using a spectrum analyzer or phase noise analyzer. When using most RF test equipment no DC bias point (0 VDC) is required for safe and proper operation. The internal 50 Ω termination the test equipment correctly terminates the LVPECL driver being measured as shown in Figure 38. When using only one LVPECL driver of a CLKoutX/CLKoutX* pair, be sure to properly terminated the unused driver.

LMK00301 30147027.gifFigure 38. Single-Ended LVPECL Operation, AC Coupling