JAJSBG5H September   2003  – November 2018 LM5007

PRODUCTION DATA.  

  1. 特長
  2. アプリケーション
  3. 概要
    1.     Device Images
      1.      代表的なアプリケーションの回路図
  4. 改訂履歴
  5. Pin Configuration and Functions
    1.     Pin Functions
  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 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Hysteretic Control Circuit Overview
      2. 7.3.2 High-Voltage Bias Supply Regulator
      3. 7.3.3 Overvoltage Comparator
      4. 7.3.4 On-Time Generator and Shutdown
      5. 7.3.5 Overcurrent Protection
      6. 7.3.6 N-Channel Buck Switch and Driver
      7. 7.3.7 Thermal Protection
      8. 7.3.8 Minimum Load Current
      9. 7.3.9 Ripple Configuration
    4. 7.4 Device Functional Modes
      1. 7.4.1 Standby Mode with VIN
      2. 7.4.2 Shutdown Mode
  8. Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Custom Design With WEBENCH® Tools
        2. 8.2.2.2 Custom Design With Excel Quickstart Tool
        3. 8.2.2.3 Feedback Resistors, RFB1 and RFB2
        4. 8.2.2.4 Switching Frequency Selection, RON
        5. 8.2.2.5 Buck Inductor, L1
        6. 8.2.2.6 Output Capacitor, COUT
        7. 8.2.2.7 Type I Ripple Circuit, RC
        8. 8.2.2.8 Input Capacitor, CIN
        9. 8.2.2.9 Current Limit, RCL
      3. 8.2.3 Application Curves
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11デバイスおよびドキュメントのサポート
    1. 11.1 デバイス・サポート
      1. 11.1.1 デベロッパー・ネットワークの製品に関する免責事項
      2. 11.1.2 WEBENCH®ツールによるカスタム設計
      3. 11.1.3 開発サポート
    2. 11.2 ドキュメントのサポート
      1. 11.2.1 関連資料
        1. 11.2.1.1 PCBレイアウトについてのリソース
        2. 11.2.1.2 熱設計についてのリソース
    3. 11.3 コミュニティ・リソース
    4. 11.4 商標
    5. 11.5 静電気放電に関する注意事項
    6. 11.6 Glossary
  12. 12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

Buck Inductor, L1

The inductor is selected to provide a current ripple of 40% to 50% of the full-load current. In addition, the peak inductor current at maximum load must be smaller than the minimum current limit threshold provided in Electrical Characteristics. The inductor current ripple is given by Equation 10.

Equation 10. LM5007 q_deltaIL_nvs252.gif

The maximum ripple is observed at the maximum input voltage. Using VIN = 75 V and ΔIL= 50% x IOUT(max) results in L1= 114 µH. Select a standard inductor value of 100 µH. The inductor current ripple ranges from 88 mA to 228 mA depending on input voltage. The peak inductor and switch current at full load are given by Equation 11.

Equation 11. LM5007 q_ILpeak_nvs252.gif

At maximum VIN, the peak inductor current is 514 mA, which is lower than the minimum current limit threshold of 535 mA. The selected inductor should be able to operate at the maximum current limit of 900 mA without saturation during startup and overload conditions.