SLVS873F June   2015  – September 2021 TPS61098 , TPS610981 , TPS610982 , TPS610985 , TPS610986 , TPS610987

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 Diagrams
    3. 8.3 Feature Description
      1. 8.3.1 Boost Controller Operation
      2. 8.3.2 Pass-Through Operation
      3. 8.3.3 LDO / Load Switch Operation
      4. 8.3.4 Start Up and Power Down
      5. 8.3.5 Over Load Protection
      6. 8.3.6 Thermal Shutdown
    4. 8.4 Device Functional Modes
      1. 8.4.1 Operation Modes by MODE Pin
        1. 8.4.1.1 Active Mode
        2. 8.4.1.2 Low Power Mode
      2. 8.4.2 Burst Mode Operation under Light Load Condition
      3. 8.4.3 Pass-Through Mode Operation
  9. 9 Applications and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 VMAIN to Power MCU and VSUB to Power Subsystem
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Device Choice
          2. 9.2.1.2.2 Maximum Output Current
          3. 9.2.1.2.3 Inductor Selection
          4. 9.2.1.2.4 Capacitor Selection
          5. 9.2.1.2.5 Control Sequence
        3. 9.2.1.3 Application Curves
      2. 9.2.2 VMAIN to Power the System in Low Power Mode
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
        3. 9.2.2.3 Application Curves
      3. 9.2.3 VSUB to Power the System in Active Mode
        1. 9.2.3.1 Design Requirements
        2. 9.2.3.2 Detailed Design Procedure
        3. 9.2.3.3 Application Curves
  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 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

Package Options

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

8.3.2 Pass-Through Operation

The TPS61098x supports automatic pass-through function for the boost converter. When the input voltage is detected higher than the pass-through threshold V(PSTH), which is around V(MAIN) set value, the boost converter enters into pass-through operation mode. In this mode, the boost converter stops switching, the rectifier is constantly turned on and the low side switch is turned off. The input voltage passes through external inductor and the internal rectifier to the output. The output voltage in this mode depends on the resistance between the input and the output, calculated as Equation 1:

Equation 1. GUID-43012967-ABB6-40E3-B92F-40929AA972F5-low.gif

where

  • RL is the DCR of external inductor
  • RDS(on)_HS is the resistance of internal rectifier

When the input voltage is lower than V(PSTH), the boost converter resumes switching to regulate the output at target value.

The TPS61098x can support automatic pass-through function in both Active mode and Low Power mode.