SLDS238B January   2018  – January  2020 TPS92611-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 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 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 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Community Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

7.3.6 Fault-Bus Output With One-Fails–All-Fail

The TPS92611-Q1 device has a fault bus for diagnostics output. In normal operation, FAULT is weakly pulled up by an internal pullup current source I(FAULT_pullup) higher than VOH(FAULT). If any fault occurs, the fault bus is strongly pulled low by the internal pulldown current source I(FAULT_pulldown). Once V(FAULT) falls below VIL(FAULT), all outputs shut down for protection. The faulty channel keeps retrying until the fault is removed.

If FAULT is externally pulled up with a current larger than I(FAULT_pulldown), the one-fails–all-fail function is disabled and only the faulty channel is turned off.

The fault bus is able to support up to 15 pieces of TPS9261x-Q1, TPS9263x-Q1, or TPS9283x-Q1 devices.

Table 1. Fault Table With DIAGEN = HIGH

FAULT BUS STATUS FAULT TYPE DETECTION MECHANISM CHANNEL STATE DEGLITCH TIME FAULT BUS FAULT HANDLING ROUTINE FAULT RECOVERY
FAULT floating or externally pulled up Open-circuit or short-to-supply V(IN) – V(OUT) < V(OPEN_th_rising) On t(OPEN_deg) Constant-current pulldown Device works normally with FAULT pin pulled low. Device sources I(retry) current when PWM is LOW. Device keeps output normal when PWＭ is HIGH. Auto recover
Short-to-ground V(OUT) < V(SG_th_rising) On t(SG_deg) Constant-current pulldown Device turns output off and retries with constant current I(retry), ignoring the PWM input. Auto recover
Over-
temperature		 TJ > T(TSD) On or off t(TSD_deg) Constant-current pulldown Devices turns output off. Auto recover
Externally pulled low Device turns output off

Table 2. Fault Table With DIAGEN = LOW

FAULT BUS STATUS FAULT TYPE DETECTION MECHANISM CHANNEL STATE DEGLITCH TIME FAULT BUS FAULT HANDLING ROUTINE FAULT RECOVERY
FAULT floating or externally pulled up Open-circuit or short-to-supply Ignored
Short-to-ground VOUT < V(SG_th_rising) On t(SG_deg) Constant-current pulldown Device turns output off and retries with constant current I(retry), ignoring the PWM input. Auto recover
Over-
temperature		 TJ > T(TSD) On or off t(TSD_deg) Constant-current pulldown Devices turns output off. Auto recover
Externally pulled low Device turns output off