SLVSI26 July   2026 TPS1HC03-Q1

PRODMIX  

  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  Input Voltage Thresholds
      2. 8.3.2  Accurate Current Sense
        1. 8.3.2.1 SNS Response Time
        2. 8.3.2.2 SNS Output Filter
        3. 8.3.2.3 Multiplexing of Current Sense Across Devices
      3. 8.3.3  Overcurrent Protection
        1. 8.3.3.1 Adjustable Current Limit
          1. 8.3.3.1.1 Current Limiting With Thermal Regulation
          2. 8.3.3.1.2 Current Limiting With No Thermal Regulation
          3. 8.3.3.1.3 Current Limit Foldback
          4. 8.3.3.1.4 Current Limit Accuracy
        2. 8.3.3.2 Thermal Shutdown
          1. 8.3.3.2.1 Relative Thermal Shutdown
          2. 8.3.3.2.2 Absolute Thermal Shutdown
      4. 8.3.4  Retry Protection Mechanism From Thermal Shutdown
      5. 8.3.5  Inductive-Load Switching-Off Clamp
      6. 8.3.6  Slower Slew Rate Option
      7. 8.3.7  Capacitive Load Charging
        1. 8.3.7.1 Adjustable Current Limiting for Inrush Control
        2. 8.3.7.2 Current Limit with Thermal Regulation for Capacitive Loads
        3. 8.3.7.3 Retry Thermal Shutdown Behavior for Capacitive Loads
        4. 8.3.7.4 Impact of DC Load on Capacitive Charging Capability
        5. 8.3.7.5 Device Capability
      8. 8.3.8  Bulb Charging
        1. 8.3.8.1 Non-Thermal Regulated Mode for Bulb Loads
        2. 8.3.8.2 Thermal Management During Bulb Inrush
        3. 8.3.8.3 Device Capability
      9. 8.3.9  Fault Detection and Reporting
        1. 8.3.9.1 Diagnostic Enable Function
        2. 8.3.9.2 FLT Reporting
        3. 8.3.9.3 FLT Timings
        4. 8.3.9.4 Fault Table
      10. 8.3.10 Full Diagnostics
        1. 8.3.10.1 Open-Load Detection
          1. 8.3.10.1.1 Channel On
          2. 8.3.10.1.2 Channel Off
        2. 8.3.10.2 Short-to-Battery Detection
        3. 8.3.10.3 Reverse-Polarity and Battery Protection
      11. 8.3.11 Full Protections
        1. 8.3.11.1 UVLO Protection
        2. 8.3.11.2 Loss of GND Protection
        3. 8.3.11.3 Loss of Power Supply Protection
        4. 8.3.11.4 Reverse Current Protection
        5. 8.3.11.5 Protection for MCU I/Os
    4. 8.4 Device Functional Modes
      1. 8.4.1 OFF
      2. 8.4.2 SLEEP
      3. 8.4.3 STANDBY
      4. 8.4.4 DIAGNOSTIC
      5. 8.4.5 ACTIVE
      6. 8.4.6 FAULT
      7. 8.4.7 LOW POWER MODE
  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

8.3.5 Inductive-Load Switching-Off Clamp

When switching an inductive load off, the inductive reactance tends to pull the output voltage negative. Excessive negative voltage can cause the power FET to break down. To protect the power FET, implement an internal clamp between drain and source, namely VDS(clamp).

Equation 6. V D S c l a m p = V V S - V O U T

During the period of demagnetization (tdecay), the power FET turns on for inductance-energy dissipation. The total energy dissipates in the high-side switch. Total energy includes the energy of the power supply (E(VS)) and the energy of the load (E(load)). If resistance is in series with inductance, some of the load energy dissipates on the resistance.

Equation 7. E H S S = E V S + E l o a d = E V S + E L - E R

When an inductive load switches off, E(HSS) causes high thermal stressing on the device. The upper limit of the power dissipation depends on the device intrinsic capacity, ambient temperature, and board dissipation condition.

TPS1HC03-Q1 Drain-to-Source Clamping StructureFigure 8-23 Drain-to-Source Clamping Structure
TPS1HC03-Q1 Inductive Load Switching-Off DiagramFigure 8-24 Inductive Load Switching-Off Diagram

From the perspective of the high-side switch, E(HSS) equals the integration value during the demagnetization period.

Equation 8. E H S S = ∫ 0 t d e c a y V D S c l a m p × I O U T t d t
Equation 9. t d e c a y = L R × ln ⁡ R × I O U T m a x + V O U T V O U T
Equation 10. E H S S = L × V V S + V O U T R 2 × R × I O U T m a x - V O U T × ln ⁡ R × I O U T m a x + V O U T V O U T

When R approximately equals 0, E(HSD) is:

Equation 11. E H S S = 1 2 × L × I O U T m a x 2 × V V S + V O U T V O U T

Note that for PWM-controlled inductive loads, adding the external freewheeling circuitry as shown in the figure below, is recommended to protect the device from repetitive power stressing. TVS is used to achieve the fast decay.

TPS1HC03-Q1 Protection with External CircuitryFigure 8-25 Protection with External Circuitry

The figure below shows the VDS clamp engaging during 5mH inductive load discharge.

TPS1HC03-Q1 5mH Inductive Load Driving (VBB = 13.5V, TAMB = 125°C) Figure 8-26 5mH Inductive Load Driving (VBB = 13.5V, TAMB = 125°C)

The following figures show maximum energy dissipation capability of the device during inductive load turn off.

TPS1HC03-Q1 Maximum Energy Dissipation for Inductive Switch OFF vs Inductance (single pulse, VBB = 13.5V, TAMB = 125°C) Figure 8-27 Maximum Energy Dissipation for Inductive Switch OFF vs Inductance (single pulse, VBB = 13.5V, TAMB = 125°C)
TPS1HC03-Q1 Maximum Energy Dissipation for Inductive Switch OFF vs Peak Current (single pulse, VBB = 13.5V, TAMB = 125°C) Figure 8-28 Maximum Energy Dissipation for Inductive Switch OFF vs Peak Current (single pulse, VBB = 13.5V, TAMB = 125°C)