ZHCSHC1B January   2018  – January  2020 TPS92612-Q1

PRODUCTION DATA.  

  1. 特性
  2. 应用
  3. 说明
    1.     典型应用图
  4. 修订历史记录
  5. Pin Configuration and Functions
    1.     Pin Functions
  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. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Device Bias
        1. 7.3.1.1 Power-On Reset (POR)
      2. 7.3.2 Constant-Current Driver
      3. 7.3.3 PWM Dimming
      4. 7.3.4 Protection
        1. 7.3.4.1 Short-to-GND Protection
        2. 7.3.4.2 Overtemperature Protection
    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
  8. Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Single-Channel LED Driver
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curve
      2. 8.2.2 Single-Channel LED Driver With Heat Sharing
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
        3. 8.2.2.3 Application Curve
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11器件和文档支持
    1. 11.1 文档支持
      1. 11.1.1 相关文档
    2. 11.2 接收文档更新通知
    3. 11.3 社区资源
    4. 11.4 商标
    5. 11.5 静电放电警告
    6. 11.6 Glossary
  12. 12机械、封装和可订购信息

Short-to-GND Protection

The TPS92612-Q1 device has LED short-to-GND protection. Short-to-GND detection monitors the output voltage when the channel is in the ON state. Once a short-to-GND LED failure is detected, the device turns off the output channel and retries automatically, ignoring the PWM input. If the retry mechanism detects removal of the LED short-to-GND fault, the device resumes normal operation.

The device monitors the V(OUT) voltage and compares it with the internal reference voltage to detect a short-to-GND failure. If V(OUT) falls below V(SG_th_rising) longer than the deglitch time of t(SG_deg), the device asserts the short-to-GND fault. During the deglitching time period, if V(OUT) rises above V(SG_th_falling), the timer is reset.

Once the device has detected a short-to-GND fault, the device turns off the output channel and retries automatically with a small current. When retrying, the device sources a small current I(retry) from IN to OUT to pull up the LED loads continuously. Once auto retry detects output voltage rising above V(SG_th_falling), the device clears the short-to-GND fault and resumes normal operation.