JAJSQL6B July   2014  – September 2023 LV284

PRODUCTION DATA  

  1.   1
  2. 特長
  3. アプリケーション
  4. 概要
  5. Revision History
  6. Pin Configuration
  7. 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 Typical Characteristics
  8. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Fixed Frequency PWM Control
      2. 7.3.2 Bootstrap Voltage (CB)
      3. 7.3.3 Setting the Ouput Voltage
      4. 7.3.4 Enable (SHDN) and VIN Undervoltage Lockout
      5. 7.3.5 Current Limit
      6. 7.3.6 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Continuous Conduction Mode
      2. 7.4.2 Eco-mode
  9. Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 5 V Output Application
        1. 8.2.1.1 Design Requirements
          1. 8.2.1.1.1 Design Guide – Step By Step Design Procedure
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Output Inductor Selection
          2. 8.2.1.2.2 Output Capacitor Selection
          3. 8.2.1.2.3 Schottky Diode Selection
          4. 8.2.1.2.4 Input Capacitor Selection
          5. 8.2.1.2.5 Bootstrap Capacitor Selection
        3. 8.2.1.3 Application Performance Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. Device and Documentation Support
    1. 9.1 ドキュメントの更新通知を受け取る方法
    2. 9.2 サポート・リソース
    3. 9.3 Trademarks
    4. 9.4 静電気放電に関する注意事項
    5. 9.5 用語集
  11. 10Mechanical, Packaging, and Orderable Information

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

Continuous Conduction Mode

The LV284 steps the input voltage down to a lower output voltage. In continuous conduction mode (when the inductor current never reaches zero at steady state), the buck regulator operates in two cycles. The power switch is connected between VIN and SW. In the first cycle of operation, the transistor is closed and the diode is reverse biased. Energy is collected in the inductor, the load current is supplied by COUT and the current through the inductor is rising. During the second cycle the transistor is open and the diode is forward biased due to the fact that the inductor current cannot instantaneously change direction. The energy stored in the inductor is transferred to the load and output capacitor. The ratio of these two cycles determines the output voltage. The output voltage is defined approximately as: D = VOUT/VIN and D' = (1-D) where D is the duty cycle of the switch, D and D' is required for design calculations.