SLVS833E March   2010  – October 2020 TPS62065 , TPS62067

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
  7. 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. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Mode Selection (TPS62065)
      2. 8.3.2 Power Good Output (TPS62067)
      3. 8.3.3 Enable
      4. 8.3.4 Clock Dithering
      5. 8.3.5 Undervoltage Lockout
      6. 8.3.6 Thermal Shutdown
    4. 8.4 Device Functional Modes
      1. 8.4.1 Soft Start
      2. 8.4.2 Power Save Mode
      3. 8.4.3 Dynamic Voltage Positioning
      4. 8.4.4 100% Duty Cycle Low Dropout Operation
      5. 8.4.5 Internal Current Limit and Fold-Back Current Limit for Short Circuit Protection
      6. 8.4.6 Output Capacitor Discharge
  9. 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 Output Voltage Setting
        2. 9.2.2.2 Output Filter Design (Inductor and Output Capacitor)
          1. 9.2.2.2.1 Inductor Selection
          2. 9.2.2.2.2 Output Capacitor Selection
          3. 9.2.2.2.3 Input Capacitor Selection
        3. 9.2.2.3 Checking Loop Stability
      3. 9.2.3 Application Curves
    3. 9.3 System Example
      1. 9.3.1 TPS62067 Adjustable 1.8-V Output
  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 Related Links
    3. 12.3 Receiving Notification of Documentation Updates
    4. 12.4 Support Resources
    5. 12.5 Trademarks
    6. 12.6 Electrostatic Discharge Caution
    7. 12.7 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

パッケージ・オプション

メカニカル・データ（パッケージ｜ピン）
サーマルパッド・メカニカル・データ
発注情報

8.4.4 100% Duty Cycle Low Dropout Operation

The device starts to enter 100% duty cycle mode as the input voltage comes close to the nominal output voltage. To maintain the output voltage, the high-side MOSFET switch is turned on 100% for one or more cycles.

With further decreasing VIN the high-side MOSFET switch is turned on completely. In this case the converter offers a low input-to-output voltage difference. This is particularly useful in battery-powered applications to achieve longest operation time by taking full advantage of the whole battery voltage range.

The minimum input voltage to maintain regulation depends on the load current and output voltage, and can be calculated as:

Equation 1. VINmin = VOmax + IOmax × (RDS(on)max + RL)

where

  • IOmax = maximum output current
  • RDS(on)max = maximum P-channel switch RDS(on)
  • RL = DC resistance of the inductor
  • VOmax = nominal output voltage plus maximum output voltage tolerance