SLUSDN8 March   2021 TPS62865 , TPS62867

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Options
  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 Power Save Mode
      2. 8.3.2 Forced PWM Mode
      3. 8.3.3 100% Duty Cycle Mode Operation
      4. 8.3.4 Soft Start
      5. 8.3.5 Switch Current Limit and HICCUP Short-Circuit Protection
      6. 8.3.6 Undervoltage Lockout
      7. 8.3.7 Thermal Shutdown
    4. 8.4 Device Functional Modes
      1. 8.4.1 Enable and Disable (EN)
      2. 8.4.2 Power Good (PG)
      3. 8.4.3 Voltage Setting and Mode Selection (VSET/MODE)
  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 Custom Design With WEBENCH® Tools
        2. 9.2.2.2 Setting The Output Voltage
        3. 9.2.2.3 Output Filter Design
        4. 9.2.2.4 Inductor Selection
        5. 9.2.2.5 Capacitor Selection
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
      1. 11.2.1 Thermal Considerations
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Third-Party Products Disclaimer
      2. 12.1.2 Development Support
        1. 12.1.2.1 Custom Design With WEBENCH® Tools
    2. 12.2 Documentation Support
      1. 12.2.1 Related Documentation
    3. 12.3 Support Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

9.2.2.4 Inductor Selection

The main parameter for the inductor selection is the inductor value, then the saturation current of the inductor. To calculate the maximum inductor current under static load conditions, Equation 4 is given.

Equation 4.
GUID-848676DC-EB22-456A-A141-E26A12C8BAE0-low.svg

where

  • IOUT,MAX is the maximum output current
  • ΔIL is the inductor current ripple
  • fSW is the switching frequency
  • L is the inductor value

It is recommended to choose a saturation current for the inductor that is approximately 20% to 30% higher than IL,MAX. In addition, DC resistance and size must also be taken into account when selecting an appropriate inductor. Table 9-4 lists recommended inductors.

Table 9-4 List of Recommended Inductors
INDUCTANCE [µH](1)CURRENT RATING [A]DIMENSIONS
[L × W × H mm]		DC RESISTANCE [mΩ]PART NUMBER
0.2218.74 × 4 × 25.81Coilcraft, XAL4020-221ME
0.24 6.6 2 × 1.6 × 1.2 13 Murata, DFE201612E-R24M
(1) See the Third-party Products disclaimer.