JAJSGD5E October   2014  – October 2018 LM5160 , LM5160A

PRODUCTION DATA.  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
    1.     Device Images
      1.      代表的な同期整流降圧アプリケーション回路
      2.      代表的なFly-Buckアプリケーション回路
  4. 4 改訂履歴
  5. 5 概要（続き）
  6. 6 Pin Configuration and Functions
    1.     Pin Functions
  7. 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 Switching Characteristics
    7. 7.7 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Control Circuit
      2. 8.3.2  VCC Regulator
      3. 8.3.3  Regulation Comparator
      4. 8.3.4  Soft Start
      5. 8.3.5  Error Amplifier
      6. 8.3.6  On-Time Generator
      7. 8.3.7  Current Limit
      8. 8.3.8  N-Channel Buck Switch and Driver
      9. 8.3.9  Synchronous Rectifier
      10. 8.3.10 Enable / Undervoltage Lockout (EN/UVLO)
      11. 8.3.11 Thermal Protection
    4. 8.4 Device Functional Modes
      1. 8.4.1 Forced Pulse Width Modulation (FPWM) Mode
      2. 8.4.2 Undervoltage Detector
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Ripple Configuration
    2. 9.2 Typical Applications
      1. 9.2.1 LM5160 Synchronous Buck (10-V to 60-V Input, 5-V Output, 1.5-A Load)
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1  Custom Design With WEBENCH® Tools
          2. 9.2.1.2.2  Feedback Resistor Divider - RFB1, RFB2
          3. 9.2.1.2.3  Switching Frequency - RON
          4. 9.2.1.2.4  Inductor - L
          5. 9.2.1.2.5  Output Capacitor - COUT
          6. 9.2.1.2.6  Series Ripple Resistor - RESR
          7. 9.2.1.2.7  VCC and Bootstrap Capacitors - CVCC, CBST
          8. 9.2.1.2.8  Input Capacitor - CIN
          9. 9.2.1.2.9  Soft-Start Capacitor - CSS
          10. 9.2.1.2.10 EN/UVLO Resistors - RUV1, RUV2
        3. 9.2.1.3 Application Curves
      2. 9.2.2 LM5160 Isolated Fly-Buck (18-V to 32-V Input, 12-V, 4.5-W Isolated Output)
        1. 9.2.2.1 LM5160 Fly-Buck Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
          1. 9.2.2.2.1 Selection of VOUT1 and Turns Ratio
          2. 9.2.2.2.2 Secondary Rectifier Diode
          3. 9.2.2.2.3 External Ripple Circuit
          4. 9.2.2.2.4 Output Capacitor - COUT2
        3. 9.2.2.3 Application Curves
      3. 9.2.3 LM5160A Isolated Fly-Buck (18-V to 32-V Input, 12-V, 4.5-W Isolated Output)
    3. 9.3 Do's and Don'ts
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12デバイスおよびドキュメントのサポート
    1. 12.1 デバイス・サポート
      1. 12.1.1 デベロッパー・ネットワークの製品に関する免責事項
      2. 12.1.2 開発サポート
        1. 12.1.2.1 WEBENCH®ツールによるカスタム設計
    2. 12.2 ドキュメントのサポート
      1. 12.2.1 関連資料
    3. 12.3 関連リンク
    4. 12.4 ドキュメントの更新通知を受け取る方法
    5. 12.5 コミュニティ・リソース
    6. 12.6 商標
    7. 12.7 静電気放電に関する注意事項
    8. 12.8 Glossary
  13. 13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

8.3.2 VCC Regulator

The LM5160 contains an internal high-voltage linear regulator with a nominal output voltage of 7.5 V (typical). The VCC regulator is internally current limited to 30 mA (minimum). This regulator supplies power to internal circuit blocks including the synchronous FET gate driver and the logic circuits. When the VCC voltage reaches the undervoltage lockout (VCC(UV)) threshold of 3.98 V (typical), the IC is enabled. An external capacitor at the VCC pin stabilizes the regulator and supplies transient VCC current to the gate drivers. An internal diode connected from VCC to BST replenishes the charge in the high-side gate drive bootstrap capacitor when the SW voltage is low.

In high input voltage applications, the power dissipated in the regulator is significant and can limit the efficiency and maximum achievable output power. The LM5160A allows the internal VCC regulator power loss to be reduced by supplying the VCC voltage through a diode from an external voltage source regulated between 9 V and 13 V. The external VCC bias can be supplied from the LM5160A converter output rail if the regulation voltage is within this range. When the VCC pin of the LM5160A is raised above the regulation voltage (7.5 V typical), the internal regulator is disabled and the power dissipation in the IC is reduced. The only difference between the LM5160 and LM5160A is the wide operating VCC voltage range of the LM5160A.