JAJSN89A December   2021  – March 2022 TPS92624-Q1

PRODUCTION DATA  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
  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 Timing Requirements
    7. 6.7 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 サポート・リソース
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

パッケージ・オプション

メカニカル・データ（パッケージ｜ピン）
サーマルパッド・メカニカル・データ
発注情報

7.3.6 Supply Control

The TPS92624-Q1 can support supply control to turn ON and OFF output current. When the voltage applied on the SUPPLY pin is higher than the LED string forward voltage plus needed headroom voltage at required current, and the PWM pin voltage is high, the output current is turned ON and well regulated. However, if the voltage applied on the SUPPLY pin is lower than V(POR_falling), the output current is turned OFF. With this feature, the power supply voltage in designed pattern can control the output current ON and OFF. The brightness is adjustable if the ON and OFF frequency is fast enough. Because of the high accuracy design of PWM threshold in TPS92624-Q1, TI recommends a resistor divider on the PWM pin to set the SUPPLY threshold higher than LED forward voltage plus required headroom voltage as shown in Figure 7-2. The headroom voltage is basically the summation of V(DROPOUT) and V(CS_REG). When the voltage on the PWM pin is higher than VIH(PWM), the output current is turned ON. However, when the voltage on the PWM is lower than VIL(PWM), the output current is turned OFF. The SUPPLY threshold voltage can be calculated by using Equation 2.

Figure 7-2 Application Schematic for Supply Control LED Brightness
Equation 2. GUID-9ACAB367-A370-45F0-98A1-06AD9674AB5D-low.gif

where

  • VIH(PWM) = 1.26 V (maximum)