SLVSH72 December   2023 TPS281C100

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Options
  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 Device Functional Modes
    4. 8.4 Working Mode
    5. 8.5 Feature Description
      1. 8.5.1 Accurate Current Sense
        1. 8.5.1.1 High Accuracy Sense Mode
      2. 8.5.2 Programmable Current Limit
        1. 8.5.2.1 Short-Circuit and Overload Protection
        2. 8.5.2.2 Capacitive Charging
      3. 8.5.3 Inductive-Load Switching-Off Clamp
      4. 8.5.4 Inductive Load Demagnetization
      5. 8.5.5 Full Protections and Diagnostics
        1. 8.5.5.1 Open-Load Detection
        2. 8.5.5.2 Thermal Protection Behavior
        3. 8.5.5.3 Undervoltage Lockout (UVLO) Protection
        4. 8.5.5.4 Reverse Polarity Protection
        5. 8.5.5.5 Protection for MCU I/Os
        6. 8.5.5.6 Diagnostic Enable Function
        7. 8.5.5.7 Loss of Ground
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
        1. 9.2.1.1 IEC 61000-4-4 EFT
        2. 9.2.1.2 IEC 61000-4-5 Surge
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Selecting RILIM
        2. 9.2.2.2 Selecting RSNS
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
        1. 9.4.1.1 EMC Considerations
      2. 9.4.2 Layout Example
        1. 9.4.2.1 PWP Layout Without a GND Network
        2. 9.4.2.2 PWP Layout With a GND Network
        3. 9.4.2.3 DNT Layout Without a GND Network
      3. 9.4.3 Thermal Considerations
  11. 10Device and Documentation Support
    1. 10.1 Receiving Notification of Documentation Updates
    2. 10.2 Support Resources
    3. 10.3 Trademarks
    4. 10.4 Electrostatic Discharge Caution
    5. 10.5 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • DNT|12
Thermal pad, mechanical data (Package|Pins)
Orderable Information

9.2.2.1 Selecting RILIM

The current limit set level TPS281C100 must allow for the maximum DC current with margin but minimize the energy in the switch and the load on the input supply during a fault condition by minimizing the current limit.

The nominal current limit should be set such that the worst case (lowest) current limit will be higher than the maximum nominal load current. If the application is a 500 mA digital output module, with the max current to be 1A, then there are two ways to set the current limit.

First way is to use the resistor value listed in the electrical characteristic table. 25 kΩ RILIM resistor setting will set the current limit minimum level to be 1.5 A, which is above the maximum nominal load current. If the high end of the setting 2.3 A is acceptable in the application, then 25 kΩ RILIM resistance can be used.

If the application wants to minimize the maximum current seen by the module as much as possible, then the current limit resistor needs to be chosen so that the minimum current limit level is as close to the maximum load current as possible. To obtain the minimum current limit to be 1 A, the typical current limit needed to be scaled for the same ratio 1 × 1.32 = 1.32 A. By linear interpolation, we can find the KCL value at 1.32 A typical current limit is 48.5 A * kΩ.

Equation 11. RILIM = KCL / ICL

The calculated value of RILIM is 36.7 kΩ, and the closest 1% standard resistor value is 36.5 kΩ.