JAJSI29 October   2019 LM5163

PRODUCTION DATA.  

  1. 1 特長
  2. 2 アプリケーション
  3. 3 概要
    1.     Device Images
      1.      代表的なアプリケーション
      2.      代表的なアプリケーション の効率、VOUT = 12V時
  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 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 Architecture
      2. 8.3.2  Internal VCC Regulator and Bootstrap Capacitor
      3. 8.3.3  Regulation Comparator
      4. 8.3.4  Internal Soft Start
      5. 8.3.5  On-Time Generator
      6. 8.3.6  Current Limit
      7. 8.3.7  N-Channel Buck Switch and Driver
      8. 8.3.8  Synchronous Rectifier
      9. 8.3.9  Enable/Undervoltage Lockout (EN/UVLO)
      10. 8.3.10 Power Good (PGOOD)
      11. 8.3.11 Thermal Protection
    4. 8.4 Device Functional Modes
      1. 8.4.1 Shutdown Mode
      2. 8.4.2 Active Mode
      3. 8.4.3 Sleep Mode
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Custom Design With WEBENCH® Tools
        2. 9.2.2.2 Switching Frequency (RRON)
        3. 9.2.2.3 Buck Inductor (LO)
        4. 9.2.2.4 Output Capacitor (COUT)
        5. 9.2.2.5 Input Capacitor (CIN)
        6. 9.2.2.6 Type 3 Ripple Network
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
      1. 11.1.1 Compact PCB Layout for EMI Reduction
      2. 11.1.2 Feedback Resistors
    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 関連資料
    3. 12.3 ドキュメントの更新通知を受け取る方法
    4. 12.4 サポート・リソース
    5. 12.5 商標
    6. 12.6 静電気放電に関する注意事項
    7. 12.7 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

9.2.2.2 Switching Frequency (RRON)

The switching frequency of the LM5163 is set by the on-time programming resistor placed at RON. As shown by Equation 15, a standard 100 kΩ, 1% resistor sets the switching frequency at 300 kHz.

Equation 15. LM5163 q_Ron_nvsb51.gif

Note that at very low duty cycles, the 50 ns minimum controllable on-time of the high-side MOSFET, tON(min), limits the maximum switching frequency. In CCM, tON(min) limits the voltage conversion step-down ratio for a given switching frequency. Use Equation 16 to calculate the minimum controllable duty cycle.

Equation 16. LM5163 q_Dmin_nvsb51.gif

Ultimately, the choice of switching frequency for a given output voltage affects the available input voltage range, solution size, and efficiency. Use Equation 17 to calculate the maximum supply voltage for a given tON(min) before switching frequency reduction occurs.

Equation 17. LM5163 q_Vin-max_nvsb51.gif