JAJSHZ4A September   2019  – February 2020 LMR36520

PRODUCTION DATA.  

  1. 特長
  2. アプリケーション
  3. 概要
    1.     Device Images
      1.      効率と出力電流との関係 VOUT = 5V、400kHz
      2.      概略回路図
  4. 改訂履歴
  5. Description
  6. Device Comparison Table
  7. Pin Configuration and Functions
    1.     Pin Functions
  8. Specifications
    1. 8.1 Absolute Maximum Ratings
    2. 8.2 ESD Ratings
    3. 8.3 Recommended Operating Conditions
    4. 8.4 Thermal Information
    5. 8.5 Electrical Characteristics
    6. 8.6 Timing Requirements
    7. 8.7 Switching Characteristics
    8. 8.8 System Characteristics
    9. 8.9 Typical Characteristics
  9. Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Power-Good Flag Output
      2. 9.3.2 Enable and Start-up
      3. 9.3.3 Current Limit and Short Circuit
      4. 9.3.4 Undervoltage Lockout and Thermal Shutdown
    4. 9.4 Device Functional Modes
      1. 9.4.1 Auto Mode
      2. 9.4.2 Forced PWM Operation
      3. 9.4.3 Dropout
      4. 9.4.4 Minimum Switch On-Time
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design 1: Low Power 24-V, 2-A Buck Converter
        1. 10.2.1.1 Design Requirements
        2. 10.2.1.2 Detailed Design Procedure
          1. 10.2.1.2.1  Choosing the Switching Frequency
          2. 10.2.1.2.2  Setting the Output Voltage
          3. 10.2.1.2.3  Inductor Selection
          4. 10.2.1.2.4  Output Capacitor Selection
          5. 10.2.1.2.5  Input Capacitor Selection
          6. 10.2.1.2.6  CBOOT
          7. 10.2.1.2.7  VCC
          8. 10.2.1.2.8  CFF Selection
          9. 10.2.1.2.9  External UVLO
          10. 10.2.1.2.10 Maximum Ambient Temperature
      2. 10.2.2 Application Curves
    3. 10.3 What to Do and What Not to Do
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
      1. 12.1.1 Ground and Thermal Considerations
    2. 12.2 Layout Example
  13. 13デバイスおよびドキュメントのサポート
    1. 13.1 デバイス・サポート
      1. 13.1.1 開発サポート
    2. 13.2 ドキュメントのサポート
      1. 13.2.1 関連資料
    3. 13.3 ドキュメントの更新通知を受け取る方法
    4. 13.4 サポート・リソース
    5. 13.5 商標
    6. 13.6 静電気放電に関する注意事項
    7. 13.7 Glossary
  14. 14メカニカル、パッケージ、および注文情報

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

Design Requirements

The following are example requirements for a typical 5-V or 3.3-V application. The input voltages are here for illustration purposes only. See the Specifications for the operating input voltage range.

Table 3. Detailed Design Parameters

DESIGN PARAMETER EXAMPLE VALUE
Input voltage 12 V to 24 V steady state, 4.2 V to 60-V transients
Output voltage 5 V
Maximum output current 0 A to 2 A
Switching frequency 400 kHz
Current consumption at 0-A load Critical: Need to ensure low current consumption to reduce battery drain
Switching frequency at 0-A load Not critical: Need fixed frequency operation at high load only

Table 4. List of Components for Design 1

VOUT FREQUENCY RFBB COUT L U1
5 V 400 kHz 24.9 kΩ 2 × 22 µF 10 µH LMR36520
3.3 V 400 kHz 43.2 kΩ 3 × 22 µF 6.8 µH LMR36520