SLVSD88L July   2016  – August 2021 TPS61099

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 Boost Controller Operation
      2. 8.3.2 Under-Voltage Lockout
      3. 8.3.3 Enable and Disable
      4. 8.3.4 Soft Start
      5. 8.3.5 Current Limit Operation
      6. 8.3.6 Output Short-to-Ground Protection
      7. 8.3.7 Over Voltage Protection
      8. 8.3.8 Down Mode Regulation and Pass-Through Operation
      9. 8.3.9 Thermal Shutdown
    4. 8.4 Device Functional Modes
      1. 8.4.1 Burst Mode Operation under Light Load Condition
      2. 8.4.2 Down Mode Regulation and Pass-Through Mode Operation
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application - 5 V Output Boost Converter
      1. 9.2.1 Design Requirements
        1. 9.2.1.1 Detailed Design Procedure
          1. 9.2.1.1.1 Custom Design With WEBENCH® Tools
          2. 9.2.1.1.2 Programming the Output Voltage
          3. 9.2.1.1.3 Maximum Output Current
          4. 9.2.1.1.4 Inductor Selection
          5. 9.2.1.1.5 Capacitor Selection
        2. 9.2.1.2 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
        1. 12.1.1.1 Custom Design With WEBENCH® Tools
      2. 12.1.2 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

8.3.1 Boost Controller Operation

The TPS61099x boost converter is controlled by a hysteretic current mode controller. This controller regulates the output voltage by keeping the inductor ripple current constant in the range of 300 mA and adjusting the offset of this inductor current depending on the output load. Since the input voltage, output voltage and inductor value all affect the rising and falling slopes of inductor ripple current, the switching frequency is not fixed and is determined by the operation condition. If the required average input current is lower than the average inductor current defined by this constant ripple, the inductor current goes discontinuously to keep the efficiency high under light load condition. Figure 8-2 illustrates the hysteretic current operation. If the load current is reduced further, the boost converter enters into Burst mode. In Burst mode, the boost converter ramps up the output voltage with several switching cycles. Once the output voltage exceeds a setting threshold, the device stops switching and goes into a sleep status. In sleep status, the device consumes less quiescent current. It resumes switching when the output voltage is below the setting threshold. It exits the Burst mode when the output current can no longer be supported in this mode. Refer to Figure 8-3 for Burst mode operation details.

To achieve high efficiency, the power stage is realized as a synchronous boost topology. The output voltage VOUT is monitored via an external or internal feedback network which is connected to the voltage error amplifier. To regulate the output voltage, the voltage error amplifier compares this feedback voltage to the internal voltage reference and adjusts the required offset of the inductor current accordingly.

GUID-B1239669-4E8E-4421-B623-8C684B146701-low.gifFigure 8-2 Hysteretic Current Operation
GUID-D3BEBBA3-EE10-4E3B-BF8A-C2D1D8B8B60A-low.gifFigure 8-3 Burst Mode Operation