SNVSBY8 March   2021 TPS92391

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  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 Logic Interface Characteristics
    7. 6.7 Timing Requirements for I2C Interface
    8.     14
    9. 6.8 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 Control Interface
      2. 7.3.2 Function Setting
      3. 7.3.3 Device Supply (VDD)
      4. 7.3.4 Enable (EN)
      5. 7.3.5 Charge Pump
      6. 7.3.6 Boost Controller
        1. 7.3.6.1 Boost Cycle-by-Cycle Current Limit
        2. 7.3.6.2 Controller Min On/Off Time
        3. 7.3.6.3 Boost Adaptive Voltage Control
          1. 7.3.6.3.1 FB Divider Using Two-Resistor Method
          2. 7.3.6.3.2 FB Divider Using Three-Resistor Method
          3. 7.3.6.3.3 FB Divider Using External Compensation
        4. 7.3.6.4 Boost Sync and Spread Spectrum
        5. 7.3.6.5 Light Load Mode
      7. 7.3.7 LED Current Sinks
        1. 7.3.7.1 LED Output Current Setting
        2. 7.3.7.2 LED Output String Configuration
        3. 7.3.7.3 LED Output PWM Clock Generation
      8. 7.3.8 Brightness Control
        1. 7.3.8.1 Brightness Control Signal Path
        2. 7.3.8.2 Dimming Mode
        3. 7.3.8.3 LED Dimming Frequency
        4. 7.3.8.4 Phase-Shift PWM Mode
        5. 7.3.8.5 Hybrid Mode
        6. 7.3.8.6 Direct PWM Mode
        7. 7.3.8.7 Sloper
        8. 7.3.8.8 PWM Detector Hysteresis
        9. 7.3.8.9 Dither
      9. 7.3.9 Protection and Fault Detections
        1. 7.3.9.1 Supply Faults
          1. 7.3.9.1.1 VIN Undervoltage Faults (VINUVLO)
          2.        51
          3. 7.3.9.1.2 VIN Overvoltage Faults (VINOVP)
          4. 7.3.9.1.3 VDD Undervoltage Faults (VDDUVLO)
          5. 7.3.9.1.4 VIN OCP Faults (VINOCP)
            1. 7.3.9.1.4.1 VIN OCP Current Limit vs. Boost Cycle-by-Cycle Current Limit
          6. 7.3.9.1.5 Charge Pump Faults (CPCAP, CP)
          7. 7.3.9.1.6 CRC Error Faults (CRCERR)
        2. 7.3.9.2 Boost Faults
          1. 7.3.9.2.1 Boost Overvoltage Faults (BSTOVPL, BSTOVPH)
          2. 7.3.9.2.2 Boost Overcurrent Faults (BSTOCP)
          3. 7.3.9.2.3 LEDSET Resistor Missing Faults (LEDSET)
          4. 7.3.9.2.4 MODE Resistor Missing Faults (MODESEL)
          5. 7.3.9.2.5 FSET Resistor Missing Faults (FSET)
          6. 7.3.9.2.6 ISET Resistor Out of Range Faults (ISET)
          7. 7.3.9.2.7 Thermal Shutdown Faults (TSD)
        3. 7.3.9.3 LED Faults
          1. 7.3.9.3.1 Open LED Faults (OPEN_LED)
          2. 7.3.9.3.2 Short LED Faults (SHORT_LED)
          3. 7.3.9.3.3 LED Short to GND Faults (GND_LED)
          4. 7.3.9.3.4 Invalid LED String Faults (INVSTRING)
          5. 7.3.9.3.5 I2C Timeout Faults
        4. 7.3.9.4 Overview of the Fault and Protection Schemes
    4. 7.4 Device Functional Modes
      1. 7.4.1  State Diagram
      2. 7.4.2  Shutdown
      3. 7.4.3  Device Initialization
      4. 7.4.4  Standby Mode
      5. 7.4.5  Power-line FET Soft Start
      6. 7.4.6  Boost Start-Up
      7. 7.4.7  Normal Mode
      8. 7.4.8  Fault Recovery
      9. 7.4.9  Latch Fault
      10. 7.4.10 Start-Up Sequence
    5. 7.5 Programming
      1. 7.5.1 I2C-Compatible Interface
      2. 7.5.2 Programming Examples
        1. 7.5.2.1 General Configuration Registers
        2. 7.5.2.2 Clearing Fault Interrupts
        3. 7.5.2.3 Disabling Fault Interrupts
        4. 7.5.2.4 Diagnostic Registers
    6. 7.6 Register Maps
      1. 7.6.1 FullMap Registers
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Full Feature Application for Display Backlight
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1  Inductor Selection
          2. 8.2.1.2.2  Output Capacitor Selection
          3. 8.2.1.2.3  Input Capacitor Selection
          4. 8.2.1.2.4  Charge Pump Output Capacitor
          5. 8.2.1.2.5  Charge Pump Flying Capacitor
          6. 8.2.1.2.6  Output Diode
          7. 8.2.1.2.7  Switching FET
          8. 8.2.1.2.8  Boost Sense Resistor
          9. 8.2.1.2.9  Power-Line FET
          10. 8.2.1.2.10 Input Current Sense Resistor
          11. 8.2.1.2.11 Feedback Resistor Divider
          12. 8.2.1.2.12 Critical Components for Design
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Application With Basic/Minimal Operation
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
        3. 8.2.2.3 Application Curves
      3. 8.2.3 SEPIC Mode Application
        1. 8.2.3.1 Design Requirements
        2. 8.2.3.2 Detailed Design Procedure
          1. 8.2.3.2.1  Inductor Selection
          2. 8.2.3.2.2  Coupling Capacitor Selection
          3. 8.2.3.2.3  Output Capacitor Selection
          4. 8.2.3.2.4  Input Capacitor Selection
          5. 8.2.3.2.5  Charge Pump Output Capacitor
          6. 8.2.3.2.6  Charge Pump Flying Capacitor
          7. 8.2.3.2.7  Switching FET
          8. 8.2.3.2.8  Output Diode
          9. 8.2.3.2.9  Switching Sense Resistor
          10. 8.2.3.2.10 Power-Line FET
          11. 8.2.3.2.11 Input Current Sense Resistor
          12. 8.2.3.2.12 Feedback Resistor Divider
          13. 8.2.3.2.13 Critical Components for Design
        3. 8.2.3.3 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 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support 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

7.3.9.4 Overview of the Fault and Protection Schemes

Table 7-9 Fault and Protection Schemes
FAULT NAMESTATUS BITCONDITIONTRIGGER FAULT INTERRUPTENTER FAULT RECOVERYACTION
VIN undervoltageVINUVLO_STATUSUVLO voltage falls below 0.787 V.YesYesDevice goes to standby and then attempts to restart once the input voltage rises above threshold.
VIN overvoltageVINOVP_STATUSVIN voltage rises above 43 V.YesYesDevice goes to standby and waits until input voltage falls below threshold before restarting.
VDD undervoltageVDDUVLO_STATUSVDD level falls below VDDUVLO threshold.YesNoDevice restarts once VDD level rises above VDDUVLO threshold.
VIN overcurrentVINOCP_STATUSVoltage across RISENSE exceeds 220 mV.YesYesDevice goes to Fault Recovery and then attempts to restart 100 ms after fault occurs.
Charge pump faultCP_STATUSCharge pump voltage level is abnormal.YesYesDevice goes to Fault Recovery and then attempts to restart 100 ms after fault occurs.
Charge pump components missingCPCAP_STATUSCharge pump is missing components.YesNoCharge pump is disabled. Charge pump fault will be reported. Device tries to keep normal operation.
Boost sync clock invalid faultBSTSYNC_STATUSDevice is enabled while a valid external SYNC clock is running. Then SYNC stops or changes to frequency < 75 kHz.YesNoDefaults to internal clock frequency selected by BST_FSET resistor. If BST_SYNC input is held high then spread spectrum is enabled. If BST_SYNC input is held low then spread spectrum is disabled.
CRC errorCRCERR_STATUSFactory default configuration for registers, options and trim bits are not correctly loaded from memory.YesNoDevice functions normally, if possible.
Boost OVP lowBSTOVPLOW_STATUSFB pin voltage rises above VFB_OVPL level.NoNoBoost stops switching until boost voltage level falls. The device remains in normal mode with LED drivers operational.
Boost OVP highBSTOVPH_STATUSFB pin voltage rises above VFB_OVPH level or DISCHARGE pin voltage rises above VBST_OVPH.YesYesDevice goes to Fault Recovery and waits until output voltage falls below threshold before restarting.
Boost overcurrentBSTOCP_STATUSFB pin voltages falls below VUVP level for 110 ms.YesYesDevice goes to Fault Recovery and then attempts to start 100 ms after fault occurs.
LEDSET detection faultLEDSET_STATUSLEDSET resistor missing or invalid.NoNoDefaults to 6-channel / 200mA configuration.
MODE detection faultMODESEL_STATUSMODE resistor missing or invalid.NoNoDefaults to phase-shift PWM mode, I2C address is 0x2A.
FSET detection faultFSET_STATUSBST_FSET or PWM_FSET resistor are missing or an invalid value.NoNoDevice keeps operating at 400-kHz switching frequency for boost converter and 305 Hz for PWM dimming frequency.
ISET resistor faultISET_STATUSISET pin voltage is pulled down to below 1V due to ISET pin resistor shorted to GNDYesNoLED_CURRENT[11:0] is written to 0x3FF. Total LED current limited to 70 mA.
Thermal shutdownTSD_STATUSJunction temperature rises above TSD threshold.YesYesDevice goes to standby and then attempts to restart once die temperature falls below threshold.
Open LED stringLED_STATUS OPEN_LEDHeadroom voltage on one or more channels is below minimum level and boost has adapted to maximum level.YesNoFaulted LED string is disabled and removed from adaptive boost control loop. String is re-enabled next power cycle.
LED internal shortLED_STATUS_SHORT_LEDHeadroom voltage on one or more channels is above the SHORTED_LED_THRESHOLD for > 5 ms while the headroom of at least one channel is still below this threshold.YesNoFaulted LED string is disabled and removed from adaptive boost control loop. String is re-enabled next power cycle.
LED short to GNDLED_STATUS_GND_LED

During PL FET SOFT START, voltage of one or more used LED output is below VHEADROOM when small test current is injected.

In BOOST_SU and Normal Stage, voltage of one or more used LED output is below VSHORTGND.and keeps still when the corresponding channel is off and small test current is injected.

YesYesDevice goes to Fault Recovery and then attempts to restart 100 ms after fault occurs.
Invalid LED string detectedINVSTRING_STATUSConfigured unused LED output is detected not short to GND.YesNoDevice functions normally, if possible.
I2C timeoutI2C_ERROR_STATUSDevice receives I2C command without STOP signal for 500 ms.YesNoDevice functions normally and waits for the next I2C command.