SLLSEP9H September   2015  – July 2019 SN6505A , SN6505B

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
    1.     Device Images
      1.      Simplified Schematic
  4. Revision History
  5. Pin Configuration and Functions
  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, SN6505A
    8. 6.8 Typical Characteristics, SN6505B
  7. Parameter Measurement Information
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Push-Pull Converter
      2. 8.3.2 Core Magnetization
    4. 8.4 Device Functional Modes
      1. 8.4.1 Start-Up Mode
        1. 8.4.1.1 Soft-Start
      2. 8.4.2 Operating Mode
      3. 8.4.3 Shutdown-Mode
      4. 8.4.4 Spread Spectrum Clocking
      5. 8.4.5 External Clock Mode
  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 Drive Capability
        2. 9.2.2.2 LDO Selection
        3. 9.2.2.3 Diode Selection
        4. 9.2.2.4 Capacitor Selection
        5. 9.2.2.5 Transformer Selection
          1. 9.2.2.5.1 V-t Product Calculation
          2. 9.2.2.5.2 Turns Ratio Estimate
          3. 9.2.2.5.3 Recommended Transformers
      3. 9.2.3 Application Curves
      4. 9.2.4 System Examples
        1. 9.2.4.1 Higher Output Voltage Designs
        2. 9.2.4.2 Application Circuits
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Third-Party Products Disclaimer
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Related Links
    4. 12.4 Receiving Notification of Documentation Updates
    5. 12.5 Community Resources
    6. 12.6 Trademarks
    7. 12.7 Electrostatic Discharge Caution
    8. 12.8 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

Detailed Design Procedure

The following recommendations on components selection focus on the design of an efficient push-pull converter with high current drive capability. Contrary to popular belief, the output voltage of the unregulated converter output drops significantly over a wide range in load current. The characteristic curve in Figure 1 and Figure 11 for example, shows that the difference between VOUT at minimum load and VOUT at maximum load exceeds a transceiver’s supply range. Therefore, in order to provide a stable, load independent supply while maintaining maximum possible efficiency the implementation of a low dropout regulator (LDO) is strongly advised.

The final converter circuit is shown in Figure 47. The measured VOUT and efficiency characteristics for the regulated and unregulated outputs are shown in Figure 2 and Figure 12.