SLVSD46A November   2017  – December 2021 TPS55160-Q1 , TPS55162-Q1 , TPS55165-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Description (continued)
  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 — External Components
    6. 7.6  Electrical Characteristics — Supply Voltage (VINP, VINL pins)
    7. 7.7  Electrical Characteristics — Reference Voltage (VOS_FB Pin) and Output Voltage (VOUT Pin)
    8. 7.8  Electrical Characteristics — Buck-Boost
    9. 7.9  Electrical Characteristics — Undervoltage and Overvoltage Lockout
    10. 7.10 Electrical Characteristics — IGN Wakeup
    11. 7.11 Electrical Characteristics — Logic Pins PS, IGN_PWRL, SS_EN
    12. 7.12 Electrical Characteristics – Overtemperature Protection
    13. 7.13 Electrical Characteristics – Power Good
    14. 7.14 Switching Characteristics — Reference Voltage (VOS_FB Pin) and Output Voltage (VOUT Pin)
    15. 7.15 Switching Characteristics — Buck-Boost
    16. 7.16 Switching Characteristics — Undervoltage and Overvoltage Lockout
    17. 7.17 Switching Characteristics — IGN Wakeup
    18. 7.18 Switching Characteristics — Logic Pins PS, IGN_PWRL, SS_EN
    19. 7.19 Switching Characteristics – Power Good
    20. 7.20 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 Spread-Spectrum Feature
      2. 8.3.2 Overcurrent Protection
      3. 8.3.3 Overtemperature Protection
      4. 8.3.4 Undervoltage Lockout and Minimum Start-Up Voltage
      5. 8.3.5 Overvoltage Lockout
      6. 8.3.6 VOUT Overvoltage Protection
      7. 8.3.7 Power-Good Pin
    4. 8.4 Device Functional Modes
      1. 8.4.1 State Diagram
      2. 8.4.2 Modes of Operation
        1. 8.4.2.1 Normal Mode
        2. 8.4.2.2 Low-Power Mode
      3. 8.4.3 Power-Up and Power-Down Sequences
      4. 8.4.4 Soft-Start Feature
      5. 8.4.5 Pulldown Resistor on VOUT
      6. 8.4.6 Output Voltage Selection
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Application Circuits for Output Voltage Configurations
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Power-Circuit Selections: CIN, L, COUT
          1. 9.2.2.1.1 Inductor Current in Step-Down Mode
          2. 9.2.2.1.2 Inductor Current in Step-Up Mode
          3. 9.2.2.1.3 Inductor Current in Buck-Boost Overlap Mode
          4. 9.2.2.1.4 Inductor Peak Current
        2. 9.2.2.2 Control-Circuit Selections
          1. 9.2.2.2.1 Bootstrap Capacitors
          2. 9.2.2.2.2 VOUT-Sense Bypass Capacitor
          3. 9.2.2.2.3 VREG Bypass Capacitor
          4. 9.2.2.2.4 PG Pullup Resistor and Delay Time
      3. 9.2.3 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 Development Support
    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
9.2.2.1.2 Inductor Current in Step-Up Mode

Use Equation 8 to calculate the inductor peak-ripple current in the step-up, or boost, mode (Ipk_boost).

Equation 8. GUID-0F4C6099-8018-45B9-857B-B6D4100B9988-low.gif

where

  • Dboost is the duty cycle in boost mode (refer to Equation 9).
Equation 9. GUID-26FD6BD3-47EA-4970-9789-62FFC29387B8-low.gif

In general, the maximum peak-ripple current occurs at 50% duty cycle. In this example, because of the power derating versus the input voltage, a few calculations can find that the maximum RMS current occurs when the input voltage is approximately 3.8 V, of which the load current is 0.8 A, according to Table 9-1. Equation 10 and Equation 11 show the peak-ripple current under this condition.

Equation 10. GUID-063F6100-986E-4AE2-8615-AC06C5F719E3-low.gif
Equation 11. GUID-38D5D889-E3D5-4268-BC84-CB8314B97AD1-low.gif

The power dissipations can be determined by the RMS current of the inductor. Use Equation 12 to calculate the RMS current of the inductor in buck mode (Irms_boost).

Equation 12. GUID-B730ADFD-36D8-4B6F-B777-FE043DF233E0-low.gif

Use Equation 13 to calculate the approximate power dissipation of the inductor in boost-mode (Ploss_L_boost).

Equation 13. GUID-35156AD8-A032-49E3-B110-E44C29D9985B-low.gif