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

8.3.1 Accurate Current Sense

The high-accuracy current-sense function allows a better real-time monitoring effect and accurate diagnostics without further calibration. A current mirror is used to source 1 / KSNS of the load current, flowing out to the external resistor between the SNS pin and GND, and reflected as voltage on the SNS pin.

KSNS is the ratio of the output current and the sense current. The accuracy values of KSNS quoted in the electrical characteristics do take into consideration temperature and supply voltage. Each device is internally calibrated while in production, so post-calibration by users is not required.

The sense resistor value, RSNS, can be chosen to maximize the range of currents needed to be measured by the system. The RSNS value must be chosen based on application need. The minimum RSNS value is bounded by the ADC minimum acceptable voltage, VADC,min, for the minimum load current needed to be measured by the system, ILOAD,min. The maximum RSNS value is bounded by the ADC maximum acceptable voltage, VADC,max, for the ISNSFH (check Electrical Characteristics for the minimum specification) during fault condition. The SNS pin current during fault condition, ISNSFH should be significantly higher than the SNS pin current at maximum load currrent (ILOAD,max), to provide sufficient headroom voltage (VHR) to determine difference between the maximum readable current and a fault condition. Use Equation 1 to calculate the value of RSNS without any external zener diode or resistor divider on SNS pin.

Equation 1. VADC,min×KSNSILOAD,min ≤ RSNS ≤ VADC,maxISNSFH

To get better resolution in current sense voltage, an external Zener diode or resistor divider can be connected to the SNS pin to clamp the SNS pin voltage to ADC maximum acceptable voltage, VADC,max during the fault condition. In this case, user needs to select RSNS resistor to achieve required headroom voltage (VHR) between the maximum readable current and a fault condition. Use Equation 2 to calculate the value of RSNS in this scenario.

Equation 2. VADC,min×KSNSILOAD,min ≤ RSNS ≤ VADC,max -VHR ×KSNSILOAD,max

In some applications, where there is a higher load current range the above applicable boundary equation can only satisfy either the lower or upper bound. In these cases, more emphasis can be put on the lower measurable current values which increases RSNS. Likewise, if the higher currents are of more interest the RSNS can be decreased. In case a GND network is used for reverse polarity protection, the voltage drop across the GND network has to be taken into account to ensure that the SNS pin voltage does not exceed the maximum acceptable ADC voltage.

TPS2HC08-Q1 Voltage Indication on the Current-Sense PinFigure 8-3 Voltage Indication on the Current-Sense Pin

The maximum current the system wants to read, ILOAD,max, must be below the current-limit threshold because after the current-limit threshold is tripped the SNS pin current goes to ISNSFH. Figure 8-4 shows the SNS pin behavior for 5A load step on channel 1 of the device with 1kΩ RSNS.

TPS2HC08-Q1 SNS Pin Voltage with Varying Load Current on Channel 1 (RSNS = 1kΩ, SEL = 0)Figure 8-4 SNS Pin Voltage with Varying Load Current on Channel 1 (RSNS = 1kΩ, SEL = 0)