JAJSNQ5 may   2023 TPS92629-Q1

PRODUCTION DATA  

  1.   1
  2. 1 特長
  3. 2 アプリケーション
  4. 3 説明
  5. 4 Revision History
  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 Typical Characteristics
  8. 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 Supply Current in Fault Mode
      2. 7.3.2  Enable and Shutdown
      3. 7.3.3  Constant-Current Output and Setting (IN)
      4. 7.3.4  Thermal Sharing Resistor (OUT and RES)
      5. 7.3.5  Brightness Control (EN/PWM and ADIM)
      6. 7.3.6  Diagnostics
        1. 7.3.6.1 LED Short-to-GND Detection
        2. 7.3.6.2 LED Open-Circuit and Short-to-Battery Detection
        3. 7.3.6.3 LED Open-Circuit and Short-to-Battery Detection Enable (DIAGEN)
        4. 7.3.6.4 Overtemperature Protection
        5. 7.3.6.5 Low Dropout Operation
      7. 7.3.7  Multi Fault Report
      8. 7.3.8  FAULT Table
      9. 7.3.9  LED Fault Summary
      10. 7.3.10 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
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Using Analog Dimming Controlled By MCU for Blind Spot Detection
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 ドキュメントの更新通知を受け取る方法
    2. 9.2 サポート・リソース
    3. 9.3 Trademarks
    4. 9.4 静電気放電に関する注意事項
    5. 9.5 用語集
  11. 10Mechanical, 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

7.3.6.1 LED Short-to-GND Detection

The TPS92629-Q1 device has LED short-to-GND detection. The LED short-to-GND detection monitors the output voltage when the output current is enabled. Once a short-to-GND LED failure is detected, the device turns off the faulty channel and retries automatically, regardless of the state of the PWM input. If the retry mechanism detects the removal of the LED short-to-GND fault, the device resumes to normal operation.

The TPS92629-Q1 monitors both V(OUT) voltage and V(RES) voltage of each channel and compares it with the internal reference voltage to detect a short-to-GND failure. If V(OUT) or V(RES) voltage falls below V(SG_th_falling) longer than the deglitch time of t(SG_deg), the device asserts the short-to-GND fault and pulls low the FAULT pin. During the deglitching time period, if V(OUTx) and V(RESx) rises above V(SG_th_rising), the timer is reset.

Once the TPS92629-Q1 has asserted a short-to-GND fault, the device turns off the faulty output channel and retries automatically with a small current. During retrying, the device sources a small current I(Retry) from SUPPLY to OUT and RES to pull up the LED loads continuously. After auto-retry detects output voltage rising above V(SG_th_rising), it clears the short-to-GND fault and resumes to normal operation. Figure 7-2 illustrates the timing for LED short-circuit detection, protection, retry and recovery.

GUID-20230505-SS0I-NMBT-WH2W-5SNTZ6VXSRG1-low.svg Figure 7-2 LED Short-to-GND Detection and Recovery Timing Diagram

The detailed information and value of each time period in Figure 7-2 is described in TIMING section of electrical characteristics table.