SLVSH18 December   2024 TPS4HC120-Q1

PRODUCTION DATA  

  1.   1
  2. Features
  3. Applications
  4. Description
  5. Pin Configuration and Functions
    1.     6
  6. Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 SNS Timing Characteristics
    7. 5.7 Switching Characteristics
    8. 5.8 Typical Characteristics
  7. Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Pin Current and Voltage Conventions
      2. 6.3.2 Low Power Mode
      3. 6.3.3 Accurate Current Sense
      4. 6.3.4 Adjustable Current Limit
      5. 6.3.5 Inductive-Load Switching-Off Clamp
      6. 6.3.6 Fault Detection and Reporting
        1. 6.3.6.1 Diagnostic Enable Function
        2. 6.3.6.2 Multiplexing of Current Sense
        3. 6.3.6.3 FAULT Reporting
        4. 6.3.6.4 Fault Table
      7. 6.3.7 Full Diagnostics
        1. 6.3.7.1 Short-to-GND and Overload Detection
        2. 6.3.7.2 Open-Load Detection
          1. 6.3.7.2.1 Channel On
          2. 6.3.7.2.2 Channel Off
        3. 6.3.7.3 Short-to-Battery Detection
        4. 6.3.7.4 Reverse-Polarity and Battery Protection
        5. 6.3.7.5 Thermal Fault Detection
          1. 6.3.7.5.1 Thermal Protection Behavior
      8. 6.3.8 Full Protections
        1. 6.3.8.1 UVLO Protection
        2. 6.3.8.2 Loss of GND Protection
        3. 6.3.8.3 Loss of Power Supply Protection
        4. 6.3.8.4 Reverse Polarity Protection
        5. 6.3.8.5 Protection for MCU I/Os
    4. 6.4 Device Functional Modes
      1. 6.4.1 Working Mode
  8. Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
      3. 7.2.3 Application Curves
    3. 7.3 EMC Transient Disturbances Test
    4. 7.4 Power Supply Recommendations
    5. 7.5 Layout
      1. 7.5.1 Layout Guidelines
      2. 7.5.2 Layout Examples
        1. 7.5.2.1 Without a GND Network
        2. 7.5.2.2 With a GND Network
  9. Device and Documentation Support
    1. 8.1 Receiving Notification of Documentation Updates
    2. 8.2 Support Resources
    3. 8.3 Trademarks
    4. 8.4 Electrostatic Discharge Caution
    5. 8.5 Glossary
  10. Revision History
  11. 10Mechanical, Packaging, and Orderable Information

Package Options

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

Detailed Design Procedure

To keep the 1A nominal current in the 0V to 4V current-sense range, calculate the R(SNS) resistor using Equation 7. To achieve better current-sense accuracy, a 1% tolerance or better resistor is preferred.

Equation 7. VADC,min × KSNS / ILOAD,min ≤ RSNS ≤ (VSNSFH - VHR) × KSNS / ILOAD,max

The design requirement listed in Table 7-2 yields 520Ω ≤ RSNS ≤ 4160Ω, and 1kΩ RSNS satisfies the requirements.

To set the adjustable current limit value, use the R(ILIM) recommended in the Current Limit Table. In this application, to leave enough margin for the current transient and ripple, a 9.76kΩ RILIM resistor satisfies the requirements.