SLVSEI1C June   2019  – October 2020 TPS62864 , TPS62866

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 I2C InterfaceTiming Characteristics
    7. 7.7 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 Start-up
      4. 8.3.4 Switch Current Limit and HICCUP Short-Circuit Protection
      5. 8.3.5 Undervoltage Lockout (UVLO)
      6. 8.3.6 Thermal Warning and Shutdown
    4. 8.4 Device Functional Modes
      1. 8.4.1 Enable and Disable (EN)
      2. 8.4.2 Output Discharge
      3. 8.4.3 Start-up Output Voltage and I2C Slave Address Selection (VSET)
      4. 8.4.4 Select Output Voltage Registers (VID)
      5. 8.4.5 Power Good (PG)
    5. 8.5 Programming
      1. 8.5.1 Serial Interface Description
      2. 8.5.2 Standard-, Fast-, and Fast-Mode Plus Protocol
      3. 8.5.3 HS-Mode Protocol
      4. 8.5.4 I2C Update Sequence
      5. 8.5.5 I2C Register Reset
    6. 8.6 Register Map
      1. 8.6.1 Slave Address Byte
      2. 8.6.2 Register Address Byte
      3. 8.6.3 VOUT Register 1
      4. 8.6.4 VOUT Register 2
      5. 8.6.5 CONTROL Register
      6. 8.6.6 STATUS Register
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 6-A Output Current Application
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Custom Design With WEBENCH® Tools
          2. 9.2.1.2.2 Setting The Output Voltage
          3. 9.2.1.2.3 Output Filter Design
          4. 9.2.1.2.4 Inductor Selection
          5. 9.2.1.2.5 Capacitor Selection
        3. 9.2.1.3 Application Curves
      2. 9.2.2 Smaller Application Solution
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
    3. 11.3 Thermal Considerations
  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 Support Resources
    4. 12.4 Receiving Notification of Documentation Updates
    5. 12.5 Trademarks
    6. 12.6 Electrostatic Discharge Caution
    7. 12.7 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

8.3.4 Switch Current Limit and HICCUP Short-Circuit Protection

The switch current limit prevents the device from high inductor current and 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, cycle by cycle, the high-side MOSFET is turned off and the low-side MOSFET is turned on, while the inductor current ramps down to the low-side MOSFET current limit.

When the high-side MOSFET current limit is triggered 32 times, the device stops switching. The device then automatically re-starts, with an internal soft 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.

The HICCUP is disabled by the CONTROL register bit Enable HICCUP. Disabling HICCUP changes the overcurrent protection to latching protection. The device stops switching after the high-side MOSFET current limit is triggered 32 times. Toggling the EN pin, removing and reapplying the input voltage, or writing to the CONTROL register bit Software Enable Device unlatches the device.