SLVSE18B June   2019  – February 2023 TPS1HB35-Q1

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
    1. 6.1 Recommended Connections for Unused Pins
  7. 7 Specifications
    1. 7.1 Recommended Operating Conditions
    2. 7.2 Electrical Characteristics
    3. 7.3 Absolute Maximum Ratings
    4. 7.4 ESD Ratings
    5. 7.5 Thermal Information
    6. 7.6 SNS Timing Characteristics
    7. 7.7 Switching Characteristics
    8. 7.8 Typical Characteristics
  8. 8 Parameter Measurement Information
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Protection Mechanisms
        1. 9.3.1.1 Thermal Shutdown
        2. 9.3.1.2 Current Limit
          1. 9.3.1.2.1 Current Limit Foldback
          2. 9.3.1.2.2 Programmable Current Limit
          3. 9.3.1.2.3 Undervoltage Lockout (UVLO)
          4. 9.3.1.2.4 VBB During Short-to-Ground
        3. 9.3.1.3 Voltage Transients
          1. 9.3.1.3.1 Load Dump
          2. 9.3.1.3.2 Driving Inductive Loads
        4. 9.3.1.4 Reverse Battery
        5. 9.3.1.5 Current Limit Behavior
        6. 9.3.1.6 Fault Event – Timing Diagrams
      2. 9.3.2 Diagnostic Mechanisms
        1. 9.3.2.1 VOUT Short-to-Battery and Open-Load
          1. 9.3.2.1.1 Detection With Switch Enabled
          2. 9.3.2.1.2 Detection With Switch Disabled
        2. 9.3.2.2 SNS Output
          1. 9.3.2.2.1 RSNS Value
            1. 9.3.2.2.1.1 High Accuracy Load Current Sense
            2. 9.3.2.2.1.2 SNS Output Filter
        3. 9.3.2.3 Fault Indication and SNS Mux
        4. 9.3.2.4 Resistor Sharing
        5. 9.3.2.5 High-Frequency, Low Duty-Cycle Current Sensing
    4. 9.4 Device Functional Modes
      1. 9.4.1 Off
      2. 9.4.2 Standby
      3. 9.4.3 Diagnostic
      4. 9.4.4 Standby Delay
      5. 9.4.5 Active
      6. 9.4.6 Fault
  10. 10Application and Implementation
    1. 10.1 Application Information
      1. 10.1.1 Ground Protection Network
      2. 10.1.2 Interface With Microcontroller
      3. 10.1.3 I/O Protection
      4. 10.1.4 Inverse Current
      5. 10.1.5 Loss of GND
      6. 10.1.6 Automotive Standards
        1. 10.1.6.1 ISO7637-2
        2. 10.1.6.2 AEC-Q100-012 Short Circuit Reliability
      7. 10.1.7 Thermal Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1 Thermal Considerations
        2. 10.2.2.2 RILIM Calculation
        3. 10.2.2.3 Diagnostics
          1. 10.2.2.3.1 Selecting the RISNS Value
    3. 10.3 Typical Application
      1. 10.3.1 Design Requirements
      2. 10.3.2 Detailed Design Procedure
      3. 10.3.3 Application Curves
    4. 10.4 Power Supply Recommendations
    5. 10.5 Layout
      1. 10.5.1 Layout Guidelines
      2. 10.5.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

9.3.1.2 Current Limit

When IOUT reaches the current limit threshold, ICL, the channel will switch off immediately. The ICL value will vary with slew rate and a fast current increase that occurs during a powered-on short circuit can temporarily go above the specified ICL value. In the case that the device remains enabled and limits IOUT, the thermal shutdown protection feature can be triggered due to the high amount of power dissipation in the device. When the switch is in the FAULT state, it will output an output current ISNSFH on the SNS pin . In addition, fault indication will occur when the switch is actively limiting current (applicable to version C).

During a short-circuit event, the device will hit the ICL value that is listed in the Electrical Characteristics table (for the given device version and RILIM) and then turn the output off or regulate the output current to protect the device. The device will register a short-circuit event when the output current exceeds ICL, however, the measured maximum current can exceed the ICL value due to the TPS1HB35-Q1 deglitch filter and turn-off time. This deglitch time is defined at 3 µs, so use the test setup described in the AEC-Q100-012 Short Circuit Reliability section, and take 3 µs before the peak value as the ICL. The device is assured to protect itself during a short-circuit event over the nominal supple voltage range (as defined in the Electrical Characteristics table) at 125°C.

The current threshold is defined for version C is different than version A or B. For version C, the current through the device continues to flow until the device hits relative thermal shutdown (TREL). For different VBBs the slope of the current will change. Therefore, the intersection point of where each of the slopes for the different VBB values is determined as the current threshold, ILIM, as shown in #T4807108-36. This behavior allows for the TPS1HB35C-Q1 to be able to charge up a 270-µF capacitor without shutting off due to hitting the current limit as versions A and B would.

GUID-20200908-CA0I-79HJ-P0M3-9D3BSQBZJZJN-low.gif Figure 9-2 Version C Current Threshold Definition