SNAS579G March   2012  – December 2014 LMK00105

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Functional Block Diagram
  4. 4 Revision History
  5. 5 Pin Configuration and Diagrams
    1.     Pin Functions
  6. 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 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Vdd and Vddo Power Supplies
      2. 7.3.2 Clock Input
        1. 7.3.2.1 Selection of Clock Input
          1. 7.3.2.1.1 CLKin/CLKin* Pins
          2. 7.3.2.1.2 OSCin/OSCout Pins
      3. 7.3.3 Clock Outputs
        1. 7.3.3.1 Output Enable Pin
        2. 7.3.3.2 Using Less than Five Outputs
    4. 7.4 Device Functional Modes
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Clock Inputs
      2. 8.1.2 Clock Outputs
    2. 8.2 Typical Applications
      1. 8.2.1 Typical Application Block Diagram
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Crystal Interface
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
        3. 8.2.2.3 Application Curves
  9. 9 Power Supply Recommendations
    1. 9.1 Power Supply Filtering
    2. 9.2 Power Supply Ripple Rejection
    3. 9.3 Power Supply Bypassing
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Ground Planes
      2. 10.1.2 Power Supply Pins
      3. 10.1.3 Differential Input Termination
      4. 10.1.4 Output Termination
    2. 10.2 Layout Example
    3. 10.3 Thermal Management
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Differential Voltage Measurement Terminology
    2. 11.2 Trademarks
    3. 11.3 Electrostatic Discharge Caution
    4. 11.4 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • RTW|24
Thermal pad, mechanical data (Package|Pins)
Orderable Information

10.3 Thermal Management

For reliability and performance reasons the die temperature should be limited to a maximum of 125°C. That is, as an estimate, TA (ambient temperature) plus device power consumption times θJA should not exceed 125°C.

The package of the device has an exposed pad that provides the primary heat removal path as well as excellent electrical grounding to a printed circuit board. To maximize the removal of heat from the package a thermal land pattern including multiple vias to a ground plane must be incorporated on the PCB within the footprint of the package. The exposed pad must be soldered down to ensure adequate heat conduction out of the package.

A recommended land and via pattern is shown in Figure 23. More information on soldering WQFN packages and gerber footprints can be obtained: www.ti.com/packaging.

To minimize junction temperature it is recommended that a simple heat sink be built into the PCB (if the ground plane layer is not exposed). This is done by including a copper area of about 2 square inches on the opposite side of the PCB from the device. This copper area may be plated or solder coated to prevent corrosion but should not have conformal coating (if possible), which could provide thermal insulation. The vias shown in Figure 23 should connect these top and bottom copper layers and to the ground layer. These vias act as “heat pipes” to carry the thermal energy away from the device side of the board to where it can be more effectively dissipated.