SNVSCC4A October   2023  – September 2024 LP5811

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Timing Requirements
    7. 5.7 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Synchronous Boost Converter
        1. 6.3.1.1 Undervoltage Lockout
        2. 6.3.1.2 Enable and Soft Start
        3. 6.3.1.3 Switching Frequency
        4. 6.3.1.4 Current Limit Operation
        5. 6.3.1.5 Boost PWM Mode
        6. 6.3.1.6 Boost PFM Mode
      2. 6.3.2 Analog Dimming
      3. 6.3.3 PWM Dimming
      4. 6.3.4 Autonomous Animation Engine Control
        1. 6.3.4.1 Animation Engine Pattern
        2. 6.3.4.2 Sloper
        3. 6.3.4.3 Animation Engine Unit (AEU)
        4. 6.3.4.4 Animation Pause Unit (APU)
      5. 6.3.5 Protections and Diagnostics
        1. 6.3.5.1 Overvoltage Protection
        2. 6.3.5.2 Output Short-to-Ground Protection
        3. 6.3.5.3 LED Open Detections
        4. 6.3.5.4 LED Short Detections
        5. 6.3.5.5 Thermal Shutdown
    4. 6.4 Device Functional Modes
    5. 6.5 Programming
    6. 6.6 Register Maps
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Application
      1. 7.2.1 Application
      2. 7.2.2 Design Parameters
      3. 7.2.3 Detailed Design Procedure
        1. 7.2.3.1 Inductor Selection
        2. 7.2.3.2 Output Capacitor Selection
        3. 7.2.3.3 Input Capacitor Selection
        4. 7.2.3.4 Program Procedure
        5. 7.2.3.5 Programming Example
      4. 7.2.4 Application Performance Plots
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
  9. 8 Device and Documentation Support
    1. 8.1 Documentation Support
    2. 8.2 Receiving Notification of Documentation Updates
    3. 8.3 Support Resources
    4. 8.4 Trademarks
    5. 8.5 Electrostatic Discharge Caution
    6. 8.6 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

7.2.3.5 Programming Example

To get the design parameters in Section 7.2.2, the following program steps can be referred.

After properly providing the power supplies to LP5811

  1. Set chip_en = 1 to enable the device. (Write 01h to register 000h)
  2. Set boost_vout = Fh to set 4.5V boost output voltage, and max_current = 1h to set 51mA maximum output LED current. (Write 1Fh to register 001h)
  3. Set led_mode = 4h to configure the LED drive mode as direct drive mode. (Write 40h to register 002h)
  4. Set lsd_threshold = 3h is recommended to avoid incorrect LSD detection. (Write 0Bh to register 00Dh)

    Let the PWM frequency, scan order, manual or autonomous mode, linear or exponential dimming curve, phase align method, vsync mode, blank time, clamp settings as default. (In other application requirements, these functions can be set)

  5. Send update command to complete configuration settings (Write 55h to register 010h)
  6. Read back config_err_status to check if the configuration is proper (Read register 300h)
  7. Enable all 12 LEDs (Write F0h to register 020h and FFh to register 021h)
  8. Set 51mA peak current for red LEDs (Write FFh to registers 035h, 038h, 03Bh, 03Eh) , and 40mA peak current for green and blue LEDs (Write CCh to registers 034h, 036h, 037h, 039h, 03Ah, 03Ch, 03Dh, 03Fh)
  9. Set 100% duty cycle to illuminate the LEDs (Write FFh to registers 044h - 04Fh)