SLDS274A September   2024  – March 2025 DRV81242-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison
  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 SPI Timing Requirements
    7. 6.7 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 Control Pins
        1. 7.3.1.1 Input Pins
        2. 7.3.1.2 nSLEEP Pin
      2. 7.3.2 Power Supply
        1. 7.3.2.1 Modes of Operation
          1. 7.3.2.1.1 Power-up
          2. 7.3.2.1.2 Sleep mode
          3. 7.3.2.1.3 Idle mode
          4. 7.3.2.1.4 Active Mode
          5. 7.3.2.1.5 Limp Home Mode
        2. 7.3.2.2 Reset condition
      3. 7.3.3 Power Stage
        1. 7.3.3.1 Switching Resistive Loads
        2. 7.3.3.2 Inductive Output Clamp
        3. 7.3.3.3 Maximum Load Inductance
        4. 7.3.3.4 Reverse Current Behavior
        5. 7.3.3.5 Switching Channels in parallel
        6. 7.3.3.6 Bulb Inrush Mode (BIM)
        7. 7.3.3.7 Integrated PWM Generator
      4. 7.3.4 Protection and Diagnostics
        1. 7.3.4.1 Undervoltage on VM
        2. 7.3.4.2 Overcurrent Protection
        3. 7.3.4.3 Over Temperature Protection
        4. 7.3.4.4 Over Temperature Warning
        5. 7.3.4.5 Over Temperature and Overcurrent Protection in Limp Home Mode
        6. 7.3.4.6 Reverse Polarity Protection
        7. 7.3.4.7 Over Voltage Protection
        8. 7.3.4.8 Output Status Monitor
        9. 7.3.4.9 Open Load Detection in ON State
          1. 7.3.4.9.1 Open Load at ON - direct channel diagnosis
          2. 7.3.4.9.2 Open Load at ON - diagnosis loop
          3. 7.3.4.9.3 OLON bit
      5. 7.3.5 SPI Communication
        1. 7.3.5.1 SPI Signal Description
          1. 7.3.5.1.1 Chip Select (nSCS)
            1. 7.3.5.1.1.1 Logic high to logic low Transition
            2. 7.3.5.1.1.2 Logic low to logic high Transition
          2. 7.3.5.1.2 Serial Clock (SCLK)
          3. 7.3.5.1.3 Serial Input (SDI)
          4. 7.3.5.1.4 Serial Output (SDO)
        2. 7.3.5.2 Daisy Chain Capability
        3. 7.3.5.3 SPI Protocol
        4. 7.3.5.4 SPI Registers
          1. 7.3.5.4.1  Standard Diagnosis Register
          2. 7.3.5.4.2  Output control register
          3. 7.3.5.4.3  Bulb Inrush Mode Register
          4. 7.3.5.4.4  Input 0 Mapping Register
          5. 7.3.5.4.5  Input 1 Mapping Register
          6. 7.3.5.4.6  Input Status Monitor Register
          7. 7.3.5.4.7  Open Load Current Control Register
          8. 7.3.5.4.8  Output Status Monitor Register
          9. 7.3.5.4.9  Open Load at ON Register
          10. 7.3.5.4.10 EN_OLON Register
          11. 7.3.5.4.11 Configuration Register
          12. 7.3.5.4.12 Output Clear Latch Register
          13. 7.3.5.4.13 FPWM Register
          14. 7.3.5.4.14 PWM0 Configuration Register
          15. 7.3.5.4.15 PWM1 Configuration Register
          16. 7.3.5.4.16 PWM_OUT Register
          17. 7.3.5.4.17 MAP_PWM Register
          18. 7.3.5.4.18 Configuration 2 Register
  9. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Suggested External Components
      2. 8.1.2 Application Plots
    2. 8.2 Typical Application
    3. 8.3 Layout
      1. 8.3.1 Layout Guidelines
      2. 8.3.2 Package Footprint Compatibility
  10. 9 Device and Documentation Support
    1. 9.1 Receiving Notification of Documentation Updates
    2. 9.2 Support Resources
    3. 9.3 Trademarks
    4. 9.4 Electrostatic Discharge Caution
    5. 9.5 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information
7.3.4.9.2 Open Load at ON - diagnosis loop

When EN_OLON bits are programmed with the value 1010b, the device starts a diagnosis loop where all auto-configurable (when used as high-side switches) channels are checked for Open Load at ON. First the internal logic checks all channels which are directly driven by the micro-controller and not configured to be driven by the internal PWM generator. Then the internal logic checks all channels which are configured to be driven by the internal PWM generator.

  • Diagnosis sequence for channels driven directly by the micro-controller
    • First channel checked: channel 2. TI recommends that the channels are ON at least tON before enabling the diagnosis loop.
    • After a time tOLONSET + tSYNC the diagnosis for the first channel is completed (OLONx bit is updated)
    • The internal multiplexer is set to the next channel. After a time tOLONSW + tSYNC the diagnosis is completed (OLONx bit is updated) for the selected channel. This step is repeated for all remaining directly driven channels.
    • If one channel is OFF when the diagnosis is performed, the corresponding OLONx is set to 0b
  • Diagnosis sequence for channels driven by the internal PWM Generators
    • These channels are checked only after all channels directly driven by micro-controller are checked
    • Channels mapped to PWM Generator 0 are checked first
    • After a time tOLONSET the channel activation (switch ON) is the trigger event to perform Open Load at ON diagnosis for the first channel
    • After a time tONMAX + tOLONSW the diagnosis for the first channel is completed (OLONx bit is updated)
    • The internal multiplexer is set to the next channel. After a time tOLONSW the diagnosis is completed (OLONx bit is updated) for the currently selected channel. This step is repeated for all remaining PWM generator driven channels.
    • If the channel is in OFF state during the PWM period, the internal logic waits for the ON state to perform the diagnosis. After a time tONMAX + tOLONSW the diagnosis for that channel is completed.
    • The minimum ON time for a reliable diagnosis is > tONMAX + tOLONSW. If the ON time is < tONMAX + tOLONSW the corresponding OLONx is set to 0b.

When the loop finishes, EN_OLON bits are set back to 1111b (default value) and OLONx bits save the last diagnosis loop result. Starting another diagnosis loop to update the register content is necessary.

DRV81242-Q1 Open Load at ON Timings (Diagnosis Loop - Channels Driven by Micro-controller) Figure 7-23 Open Load at ON Timings (Diagnosis Loop - Channels Driven by Micro-controller)
DRV81242-Q1 Open Load at ON Timings (Diagnosis Loop - Channels driven by Internal PWM Generators) Figure 7-24 Open Load at ON Timings (Diagnosis Loop - Channels driven by Internal PWM Generators)