SLDS269A March   2022  – May 2022 LP5891

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 Timing Requirements
    7. 6.7 Switching Characteristics
    8. 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 Independent and Stackable Mode
        1. 7.3.1.1 Independent Mode
        2. 7.3.1.2 Stackable Mode
      2. 7.3.2 Current Setting
        1. 7.3.2.1 Brightness Control (BC) Function
        2. 7.3.2.2 Color Brightness Control (CC) Function
        3. 7.3.2.3 Choosing BC/CC for a Different Application
      3. 7.3.3 Frequency Multiplier
      4. 7.3.4 Line Transitioning Sequence
      5. 7.3.5 Protections and Diagnostics
        1. 7.3.5.1 Thermal Shutdown Protection
        2. 7.3.5.2 IREF Resistor Short Protection
        3. 7.3.5.3 LED Open Load Detection and Removal
          1. 7.3.5.3.1 LED Open Detection
          2. 7.3.5.3.2 Read LED Open Information
          3. 7.3.5.3.3 LED Open Caterpillar Removal
        4. 7.3.5.4 LED Short and Weak Short Circuitry Detection and Removal
          1. 7.3.5.4.1 LED Short/Weak Short Detection
          2. 7.3.5.4.2 Read LED Short Information
          3. 7.3.5.4.3 LSD Caterpillar Removal
    4. 7.4 Device Functional Modes
    5. 7.5 Continuous Clock Series Interface
      1. 7.5.1 Data Validity
      2. 7.5.2 CCSI Frame Format
      3. 7.5.3 Write Command
        1. 7.5.3.1 Chip Index Write Command
        2. 7.5.3.2 VSYNC Write Command
        3. 7.5.3.3 MPSM Write Command
        4. 7.5.3.4 Standby Clear and Enable Command
        5. 7.5.3.5 Soft_Reset Command
        6. 7.5.3.6 Data Write Command
      4. 7.5.4 Read Command
    6. 7.6 PWM Grayscale Control
      1. 7.6.1 Grayscale Data Storage and Display
        1. 7.6.1.1 Memory Structure Overview
        2. 7.6.1.2 Details of Memory Bank
        3. 7.6.1.3 Write a Frame Data into Memory Bank
      2. 7.6.2 PWM Control for Display
    7. 7.7 Register Maps
      1. 7.7.1  FC0
      2. 7.7.2  FC1
      3. 7.7.3  FC2
      4. 7.7.4  FC3
      5. 7.7.5  FC4
      6. 7.7.6  FC14
      7. 7.7.7  FC15
      8. 7.7.8  FC16
      9. 7.7.9  FC17
      10. 7.7.10 FC18
      11. 7.7.11 FC19
      12. 7.7.12 FC20
      13. 7.7.13 FC21
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
        1. 8.2.1.1 System Structure
        2. 8.2.1.2 SCLK Frequency
        3. 8.2.1.3 Internal GCLK Frequency
        4. 8.2.1.4 Line Switch Time
        5. 8.2.1.5 Blank Time Removal
        6. 8.2.1.6 BC and CC
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Chip Index Command
        2. 8.2.2.2 FC Registers Settings
        3. 8.2.2.3 Grayscale Data Write
        4. 8.2.2.4 VSYNC Command
        5. 8.2.2.5 LED Open/Short Read
      3. 8.2.3 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 Documentation Support
      1. 11.1.1 Related Documentation
    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

7.6.1.3 Write a Frame Data into Memory Bank

After power on, the LP5891 internal flag BANK_SEL, and counters LINE_COUNT, CHANNEL_COUNT, are all initialized to 0. Thus, the memory unit of channel R0/G0/B0, locating in line 0 of BANK A, is selected to restore the data transimitted the first time after VSYNC command.

When the first WRTGS command is received, all the data in the common shift register is latched into the memory unit of channel R0/G0/B0, locating in line 0 of BANK A. Then CHANNEL_COUNT increases by 1 and LINE_COUNT stays the same. Thus, the memory unit of channel R1/G1/B1, locating in line 0 of BANK A, is selected to restore the data transimitted the second time after VSYNC command.

When the second WRTGS command is received, all the data in the common shift register is latched into the memory unit of channel R1/G1/B1, locating in line 0 of BANK A. Then CHANNEL_COUNT increases by 1 and LINE_COUNT stays the same. Thus, the memory unit of channel R2/G2/B2, locating in line 0 of BANK A, is selected to restore the data transimitted the third time after VSYNC command.

Repeat the grayscale-data-write operation until the 16th WRTGS command is received. Then CHANNEL_COUNT is reset to 0 and LINE_COUNT increases by 1. Thus, the memory unit of channel R0/G0/B0, locating in line 1 of BANK A, is selected to restore the data transimitted the 17th time after VSYNC command.

Repeat this operation for each line until the LINE_COUNT exceeds the number of scan lines set in the SCAN_NUM (See FC0 register bit21-16 ) and all scan lines have been updated with new GS data, which means one frame of GS data is restored into the memory BANK. Then the LINE_COUNT is reset to 0.