SLUSEE5D January   2022  – April 2024 TPS4811-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 Switching Characteristics
    7. 6.7 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  Charge Pump and Gate Driver output (VS, PU, PD, BST, SRC)
      2. 8.3.2  Capacitive Load Driving
        1. 8.3.2.1 FET Gate Slew Rate Control
        2. 8.3.2.2 Using Precharge FET - (with TPS48111-Q1 Only)
      3. 8.3.3  Short-Circuit Protection
        1. 8.3.3.1 Overcurrent Protection With Auto-Retry
        2. 8.3.3.2 Overcurrent Protection With Latch-Off
      4. 8.3.4  Short-Circuit Protection
      5. 8.3.5  Analog Current Monitor Output (IMON)
      6. 8.3.6  Overvoltage (OV) and Undervoltage Protection (UVLO)
      7. 8.3.7  Device Functional Mode (Shutdown Mode)
      8. 8.3.8  Remote Temperature sensing and Protection (DIODE)
      9. 8.3.9  Output Reverse Polarity Protection
      10. 8.3.10 TPS4811x-Q1 as a Simple Gate Driver
  10. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application: Driving HVAC PTC Heater Load on KL40 Line in Power Distribution Unit
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curves
    3. 9.3 Typical Application: Driving B2B FETs With Pre-charging the Output Capacitance
      1. 9.3.1 Design Requirements
      2. 9.3.2 External Component Selection
      3. 9.3.3 Application Curves
    4. 9.4 Power Supply Recommendations
    5. 9.5 Layout
      1. 9.5.1 Layout Guidelines
      2. 9.5.2 Layout Example
  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

9.5.1 Layout Guidelines

  • The sense resistor (RSNS) must be placed close to the TPS4811x-Q1 and then connect RSNS using the Kelvin techniques. Refer to Choosing the Right Sense Resistor Layout for more information on the Kelvin techniques.

  • For all the applications, TI recommends a 0.1 µF or higher value ceramic decoupling capacitor between VS terminal and GND. Consider adding RC network at the supply pin (VS) of the controller to improve decoupling against the power line disturbances.

  • The high current path from the board’s input to the load, and the return path, must be parallel and close to each other to minimize loop inductance.

  • The external MOSFETs must be placed close to the controller such that the GATE of the MOSFETs are close to PU/PD pins to form short GATE loop. Consider adding a place holder for a resistor in series with the Gate of each external MOSFET to damp high frequency oscillations if need arises.

  • Place a TVS diode at the input to clamp the voltage transients during hot-plug and fast turn-off events.

  • The external boot-strap capacitor must be placed close to BST and SRC pins to form very short loop.

  • The ground connections for the various components around the TPS4811x-Q1 must be connected directly to each other, and to the TPS4811x-Q1’s GND, and then connected to the system ground at one point. Do not connect the various component grounds to each other through the high current ground line.

  • The DIODE pin sources current to measure the temperature. TI recommends BJT MMBT3904 to use as a remote temperature sense element. Take care in the PCB layout to keep the parasitic resistance between the DIODE pin and the MMBT3904 low so as not to degrade the measurement. In addition, TI recommends to make a Kelvin connection from the emitter of the MMBT3904 to the GND of the part to ensure an accurate measurement. Additionally, a small 1000 pF bypass capacitor must be placed in parallel with the MMBT3904 to reduce the effects of noise.