SLVSFS4A December   2021  – June 2022 TPS92623-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 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 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Power Supply (SUPPLY)
        1. 7.3.1.1 Power-On Reset (POR)
        2. 7.3.1.2 Suppply Current in Fault Mode
      2. 7.3.2  Enable and Shutdown
      3. 7.3.3  Constant-Current Output and Setting (INx)
      4. 7.3.4  Thermal Sharing Resistor (OUTx and RESx)
      5. 7.3.5  PWM Control (PWMx)
      6. 7.3.6  Supply Control
      7. 7.3.7  Diagnostics
        1. 7.3.7.1 LED Short-to-GND Detection
        2. 7.3.7.2 LED Open-Circuit Detection
        3. 7.3.7.3 LED Open-Circuit Detection Enable (DIAGEN)
        4. 7.3.7.4 Overtemperature Protection
        5. 7.3.7.5 Low Dropout Operation
      8. 7.3.8  FAULT Bus Output with One-Fails-All-Fail
      9. 7.3.9  FAULT Table
      10. 7.3.10 LED Fault Summary
      11. 7.3.11 IO Pins Inner Connection
    4. 7.4 Device Functional Modes
      1. 7.4.1 Undervoltage Lockout, V(SUPPLY) < V(POR_rising)
      2. 7.4.2 Normal Operation V(SUPPLY) ≥ 4.5 V
      3. 7.4.3 Low-Voltage Dropout Operation
      4. 7.4.4 Fault Mode
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 BCM Controlled Rear Lamp With One-Fails-All-Fail Setup
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Independent PWM Controlled Rear Lamp By MCU
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
        3. 8.2.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Receiving Notification of Documentation Updates
    2. 11.2 Support Resources
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

7.3.4 Thermal Sharing Resistor (OUTx and RESx)

The TPS92623-Q1 device provides two current output paths for each channel. Current flows from the supply through the R(SNSx) resistor into the integrated current regulation circuit and to the LEDs through OUTx pin and RESx pin. The current output on both OUTx pin and RESx pin is independently regulated to achieve total required current output. The summed current of OUTx and RESx is equal to the current through the R(SNSx) resistor in the channel. The OUTx connects to anode of LEDs load in serial directly, however RESx connects to the LEDs through an external resistor to share part of the power dissipation and reduce the thermal accumulation in TPS92623-Q1.

The integrated independent current regulation in TPS92623-Q1 dynamically adjusts the output current on both OUTx and RESx output to maintain the stable summed current for LED. The TPS92623-Q1 always regulates the current output to the RESx pin as much as possible until the RESx current path is saturated, and the rest of required current is regulated out of the OUTx. As a result, the most of the current to LED outputs through the RESx pin when the voltage dropout is large between SUPPLY and LED required total forward voltage. In the opposite case, the most of the current to LED outputs through the OUTx pin when the voltage headroom is relative low between SUPPLY and LED required forward voltage.