SLVSHX5A July   2025  – December 2025 TPS2HC08-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  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 SNS Timing Characteristics
    7. 6.7 Switching Characteristics
    8. 6.8 Typical Characteristics
  8. 7 Parameter Measurement Information
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Accurate Current Sense
        1. 8.3.1.1 SNS Response Time
        2. 8.3.1.2 SNS Output Filter
        3. 8.3.1.3 Multiplexing of Current Sense Across Channels
        4. 8.3.1.4 Multiplexing of Current Sense Across Devices
      2. 8.3.2  Overcurrent Protection
        1. 8.3.2.1 Adjustable Current Limit
          1. 8.3.2.1.1 Current Limiting With Thermal Regulation
          2. 8.3.2.1.2 Current Limiting With No Thermal Regulation
          3. 8.3.2.1.3 Current Limit Foldback
          4. 8.3.2.1.4 Current Limit Accuracy
        2. 8.3.2.2 Thermal Shutdown
          1. 8.3.2.2.1 Relative Thermal Shutdown
          2. 8.3.2.2.2 Absolute Thermal Shutdown
      3. 8.3.3  Retry Protection Mechanism From Thermal Shutdown
        1. 8.3.3.1 Reliable Switch-On Behavior
      4. 8.3.4  Inductive-Load Switching-Off Clamp
      5. 8.3.5  Slower Slew Rate Option
      6. 8.3.6  Capacitive Load Charging
        1. 8.3.6.1 Adjustable Current Limiting for Inrush Control
        2. 8.3.6.2 Current Limit with Thermal Regulation for Capacitive Loads
        3. 8.3.6.3 Retry Thermal Shutdown Behavior for Capacitive Loads
        4. 8.3.6.4 Impact of DC Load on Capacitive Charging Capability
        5. 8.3.6.5 Device Capability
      7. 8.3.7  Bulb Charging
        1. 8.3.7.1 Non-Thermal Regulated Mode for Bulb Loads
        2. 8.3.7.2 Thermal Management During Bulb Inrush
        3. 8.3.7.3 Device Capability
      8. 8.3.8  Fault Detection and Reporting
        1. 8.3.8.1 Diagnostic Enable Function
        2. 8.3.8.2 FLT Reporting
        3. 8.3.8.3 FLT Timings
        4. 8.3.8.4 Fault Table
      9. 8.3.9  Full Diagnostics
        1. 8.3.9.1 Open-Load Detection
          1. 8.3.9.1.1 Channel On
          2. 8.3.9.1.2 Channel Off
        2. 8.3.9.2 Short-to-Battery Detection
        3. 8.3.9.3 Reverse-Polarity and Battery Protection
      10. 8.3.10 Full Protections
        1. 8.3.10.1 UVLO Protection
        2. 8.3.10.2 Loss of GND Protection
        3. 8.3.10.3 Loss of Power Supply Protection
        4. 8.3.10.4 Reverse Current Protection
        5. 8.3.10.5 Protection for MCU I/Os
    4. 8.4 Device Functional Modes
  10. 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 EMC Transient Disturbances Test
      3. 9.2.3 Transient Thermal Performance
      4. 9.2.4 Application Curves
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Examples
        1. 9.4.2.1 Without a GND Network
        2. 9.4.2.2 With a GND Network
      3. 9.4.3 Wettable Flank Package
  11. 10Device and Documentation Support
    1. 10.1 Third-Party Products Disclaimer
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Support Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

8.3.2.1 Adjustable Current Limit

The TPS2HC08-Q1 offers a high accuracy, adjustable current which enables higher reliability and provides protection to the power supply during a short circuit or power up with large capacitance. An adjustable current limit can also save system costs by reducing PCB traces, connector size, and the capacity of the preceding power stage by setting the current limit at a lower level.

The current limit of the device can be adjusted via an external resistor on the ILIM pin. The value which is set by the ILIM pin is applied to both the channels. The device provides ILIM settings with a thermal regulated current limit which adjusts the current limit level based on the relative temperature of the FET and the controller. This avoids fast heating of the FET and delays the trigger of relative thermal shutdown, which enables the device to charge up large capacitors at startup. With ILIM pin shorted to GND, the device current limit can be configured without thermal regulation where the device limits the current at the set ILIM value. Table 8-2 details the different settings that are possible based on the ILIM pin configuration.

Table 8-2 Current Limit Settings Through ILIM Pin
RLIM VALUE on ILIM pinTYP ICL = KCL / RLIMTHERMAL REGULATION
ILIM = GND or RLIM< 20kΩMaximum setting of 25ADisabled
RLIM = 20kΩ25AEnabled
20kΩ < RLIM < 66.66 kΩ ICL = KCL / RLIM Enabled
RLIM = 66.66kΩ7.5AEnabled
ILIM = Open or RLIM > 66.66kΩMinimum setting of 7.5AEnabled

The device also offers a fast-trip circuit breaker function which is used when a short-circuit occurs while a channel is enabled which is also known as a hot-short. Once the ICB threshold is reached, the device quickly turns off the channel to protect the internal MOSFET. Additionally, the device provides a current limit foldback function at higher voltages to help protect the internal power MOSFETs during high VDS events.

The different overcurrent events that can occur in a system are:

  • hot-short
  • enable into short
  • current overload (slow creep)

A hot-short occurs when a channel is enabled and a short-circuit condition is applied to the output of a channel. Enabling in to short occurs when there is already a short on the output of the MOSFET and the channel is enabled into the short-circuit condition. Current overload or also known as slow creep can occur if there is a slow rising overcurrent event at the output.

The next sections describe how the current limiting with thermal regulation and without thermal regulation work along with the circuit breaker and thermal shutdown functions to help protect against the various overcurrent conditions that can occur.