SLDS233B October   2017  – January 2020 TPS92610-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Typical Application Diagram
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin 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 Device Bias
        1. 7.3.1.1 Power-On Reset (POR)
        2. 7.3.1.2 Low-Quiescent-Current Fault Mode
      2. 7.3.2 Constant-Current Driver
      3. 7.3.3 Device Enable
      4. 7.3.4 PWM Dimming
      5. 7.3.5 Diagnostics
        1. 7.3.5.1 DIAGEN
        2. 7.3.5.2 Low-Dropout Mode
        3. 7.3.5.3 Open-Circuit Detection
        4. 7.3.5.4 Short-to-GND Detection
        5. 7.3.5.5 Single-LED-Short Detection
        6. 7.3.5.6 Overtemperature Protection
      6. 7.3.6 FAULT Bus Output With One-Fails–All-Fail
    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
      4. 7.4.4 Fault Mode
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Single-Channel LED Driver With Full Diagnostics
        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. 9 Layout
    1. 9.1 Layout Guidelines
    2. 9.2 Layout Example
  10. 10Device and Documentation Support
    1. 10.1 Documentation Support
      1. 10.1.1 Related Documentation
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Community Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary
  11. 11Mechanical, Packaging, and Orderable Information

Package Options

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

7.3.5.3 Open-Circuit Detection

The TPS92610-Q1 device has LED open-circuit detection. Open-circuit detection monitors the output voltage when the channel is in the ON state. Open-circuit detection is only enabled when DIAGEN is HIGH. A short-to-battery fault is also detected as an LED open-circuit fault.

The device monitors dropout-voltage differences between the IN and OUT pins when PWM is HIGH. The voltage difference V(IN) – V(OUT) is compared with the internal reference voltage V(OPEN_th_rising) to detect an LED open-circuit failure. If V(IN) – V(OUT) falls below the V(OPEN_th_rising) voltage longer than the deglitch time of t(OPEN_deg), the device asserts an open-circuit fault. Once an LED open-circuit failure is detected, the constant-current source pulls the fault bus down. During the deglitch time period, if V(IN) – V(OUT) rises above V(OPEN_th_falling), the deglitch timer is reset.

When the device is in auto-retry, the device keeps the output ON to retry if the PWM input is HIGH; the device sources a small current I(retry) from IN to OUT when PWM input is LOW. In either scenario, once a faulty channel recovers, the device resumes normal operation and releases the FAULT pulldown.