JAJSOJ5 October   2023 LP5811

PRODUCTION DATA  

  1.   1
  2. 1 特長
  3. 2 アプリケーション
  4. 3 概要
  5. 4 Revision History
  6. 5 Device Comparison
  7. 6 Pin Configuration and Functions
  8. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Timing Requirements
  9. 8 Typical Characteristics
  10. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Synchronous Boost Converter
        1. 9.3.1.1 Undervoltage Lockout
        2. 9.3.1.2 Enable and Soft Start
        3. 9.3.1.3 Switching Frequency
        4. 9.3.1.4 Current Limit Operation
        5. 9.3.1.5 Boost PWM Mode
        6. 9.3.1.6 Boost PFM Mode
      2. 9.3.2 Analog Dimming
      3. 9.3.3 PWM Dimming
      4. 9.3.4 Autonomous Animation Engine Control
        1. 9.3.4.1 Animation Engine Pattern
        2. 9.3.4.2 Sloper
        3. 9.3.4.3 Animation Engine Unit (AEU)
        4. 9.3.4.4 Animation Pause Unit (APU)
      5. 9.3.5 Protections and Diagnostics
        1. 9.3.5.1 Overvoltage Protection
        2. 9.3.5.2 Output Short-to-Ground Protection
        3. 9.3.5.3 LED Open Detections
        4. 9.3.5.4 LED Short Detections
        5. 9.3.5.5 Thermal Shutdown
    4. 9.4 Device Functional Modes
    5. 9.5 Programming
    6. 9.6 Register Maps
  11. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Application
      2. 10.2.2 Design Parameters
      3. 10.2.3 Detailed Design Procedure
        1. 10.2.3.1 Inductor Selection
        2. 10.2.3.2 Output Capacitor Selection
        3. 10.2.3.3 Input Capacitor Selection
        4. 10.2.3.4 Program Procedure
        5. 10.2.3.5 Programming Example
      4. 10.2.4 Application Performance Plots
    3. 10.3 Power Supply Recommendations
    4. 10.4 Layout
      1. 10.4.1 Layout Guidelines
      2. 10.4.2 Layout Example
  12. 11Device and Documentation Support
    1. 11.1 Documentation Support
    2. 11.2 ドキュメントの更新通知を受け取る方法
    3. 11.3 サポート・リソース
    4. 11.4 Trademarks
    5. 11.5 静電気放電に関する注意事項
    6. 11.6 用語集

パッケージ・オプション

メカニカル・データ（パッケージ｜ピン）
サーマルパッド・メカニカル・データ
発注情報

9.3.1.2 Enable and Soft Start

When the input voltage is above the UVLO rising threshold 1.8 V and the EN pin is pulled to a voltage above 1.2 V, the boost of LP5811 is enabled and starts up. At the beginning, the LP5811 charges the boost output capacitor with a constant current when the output voltage is below 0.4 V. When the output voltage is charged above 0.4 V, the LP5811 has capability to drive 200 mA load. After the output voltage reaches the input voltage, the boost of LP5811 starts switching, and the output voltage continually ramps up to default voltage 3 V. The typical start-up time is 450 μs from EN pulled high to output reaching default voltage 3 V, at the application that input voltage is 2.5 V, output effective capacitance is 10 μF, and no load. When the EN is below 0.42 V, the internal enable comparator turns the device into shutdown mode. In the shutdown mode, the device is entirely turned off and the output is disconnected from input power supply.