SLVSD94F November   2017  – November 2024 TPS62088 , TPS62088A , TPS62089A

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Options
  6. 5 Pin Configuration and Functions
  7. 6 Specifications
    1. 6.1 Absolute Maximum Ratings 
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information 
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Power Save Mode
      2. 7.3.2 Pulse Width Modulation (PWM) Operation
      3. 7.3.3 100% Duty Cycle Low Dropout Operation
      4. 7.3.4 Soft Start
      5. 7.3.5 Switch Current Limit and HICCUP Short-Circuit Protection
      6. 7.3.6 Undervoltage Lockout
      7. 7.3.7 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Enable and Disable
      2. 7.4.2 Power Good
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Custom Design With WEBENCH® Tools
        2. 8.2.2.2 Setting The Output Voltage
        3. 8.2.2.3 Feedforward Capacitor
        4. 8.2.2.4 Output Filter Design
        5. 8.2.2.5 Inductor Selection
        6. 8.2.2.6 Capacitor Selection
      3. 8.2.3 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
        1. 8.4.2.1 Thermal Considerations
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Third-Party Products Disclaimer
      2. 9.1.2 Development Support
        1. 9.1.2.1 Custom Design With WEBENCH® Tools
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
    3. 9.3 Receiving Notification of Documentation Updates
    4. 9.4 Support Resources
    5. 9.5 Trademarks
    6. 9.6 Electrostatic Discharge Caution
    7. 9.7 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

7.3.5 Switch Current Limit and HICCUP Short-Circuit Protection

The switch current limit prevents the device from high inductor current and from drawing excessive current from the battery or input voltage rail. Excessive current can occur with a shorted or saturated inductor or a heavy load or shorted output circuit condition. If the inductor current reaches the threshold ILIM, the high-side MOSFET is turned off and the low-side MOSFET remains off, while the inductor current flows through the body diode and quickly ramps down.

When this switch current limits is triggered 32 times, the device stops switching. The device then automatically starts a new start-up after a typical delay time of 128 µs has passed. This is named HICCUP short-circuit protection. The device repeats this mode until the high load condition disappears.

In forced PWM devices, a negative current limit (ILIMN) is enabled to prevent excessive current flowing backwards to the input. When the inductor current reaches ILIMN, the low-side MOSFET turns off and the highside MOSFET turns on and kept on until TON time expires.