JAJSAY9L February   2009  – May 2018 LM26420

PRODUCTION DATA.  

  1. 特長
  2. アプリケーション
  3. 概要
    1.     Device Images
      1.      LM26420デュアル降圧DC/DCコンバータ
      2.      LM26420の効率(最高93%)
  4. 改訂履歴
  5. Pin Configuration and Functions
    1.     Pin Functions: 16-Pin WQFN
    2.     Pin Functions 20-Pin HTSSOP
  6. Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings (LM26420X/Y)
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics Per Buck
    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 Soft Start
      2. 7.3.2 Power Good
      3. 7.3.3 Precision Enable
    4. 7.4 Device Functional Modes
      1. 7.4.1 Output Overvoltage Protection
      2. 7.4.2 Undervoltage Lockout
      3. 7.4.3 Current Limit
      4. 7.4.4 Thermal Shutdown
  8. Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Programming Output Voltage
      2. 8.1.2 VINC Filtering Components
      3. 8.1.3 Using Precision Enable and Power Good
      4. 8.1.4 Overcurrent Protection
    2. 8.2 Typical Applications
      1. 8.2.1 LM26420X 2.2-MHz, 0.8-V Typical High-Efficiency Application Circuit
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Custom Design With WEBENCH® Tools
          2. 8.2.1.2.2 Inductor Selection
          3. 8.2.1.2.3 Input Capacitor Selection
          4. 8.2.1.2.4 Output Capacitor
          5. 8.2.1.2.5 Calculating Efficiency and Junction Temperature
        3. 8.2.1.3 Application Curves
      2. 8.2.2 LM26420X 2.2-MHz, 1.8-V Typical High-Efficiency Application Circuit
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
        3. 8.2.2.3 Application Curves
      3. 8.2.3 LM26420X 2.2-MHz, 2.5-V Typical High-Efficiency Application Circuit
        1. 8.2.3.1 Design Requirements
        2. 8.2.3.2 Detailed Design Procedure
        3. 8.2.3.3 Application Curves
      4. 8.2.4 LM26420Y 550 kHz, 0.8-V Typical High-Efficiency Application Circuit
        1. 8.2.4.1 Design Requirements
        2. 8.2.4.2 Detailed Design Procedure
        3. 8.2.4.3 Application Curves
      5. 8.2.5 LM26420Y 550-kHz, 1.8-V Typical High-Efficiency Application Circuit
        1. 8.2.5.1 Design Requirements
        2. 8.2.5.2 Detailed Design Procedure
        3. 8.2.5.3 Application Curves
      6. 8.2.6 LM26420Y 550-kHz, 2.5-V Typical High-Efficiency Application Circuit
        1. 8.2.6.1 Design Requirements
        2. 8.2.6.2 Detailed Design Procedure
        3. 8.2.6.3 Application Curves
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Thermal Considerations
      1. 10.3.1 Method 1: Silicon Junction Temperature Determination
      2. 10.3.2 Thermal Shutdown Temperature Determination
  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
    2. 11.2 ドキュメントのサポート
      1. 11.2.1 関連資料
    3. 11.3 ドキュメントの更新通知を受け取る方法
    4. 11.4 コミュニティ・リソース
    5. 11.5 商標
    6. 11.6 静電気放電に関する注意事項
    7. 11.7 Glossary
  12. 12メカニカル、パッケージ、および注文情報

Typical Characteristics

All curves taken at VIN = 5 V with configuration in typical application circuits shown in Application and Implementation. TJ = 25°C, unless otherwise specified.
LM26420 30069682.png
Figure 1. Efficiency vs Load, X Option
LM26420 LM26420_Efficiency_Up_to_93_Percent.png
Figure 3. Efficiency vs Load, X Option
LM26420 30069690.png
Figure 5. Efficiency vs Load, X Option
LM26420 30069688.png
Figure 7. Efficiency vs Load, X Option
LM26420 30069641.png
Figure 9. Efficiency vs Load, X Option
LM26420 30069643_nvs579.gif
VIN = 5 V VOUT = 1.8 V
Figure 11. Load Regulation (All Options)
LM26420 30069627_nvs579.gif
VOUT = 1.8 V IOUT = 1000 mA
Figure 13. Line Regulation, X Option
LM26420 30069647.png
Figure 15. Oscillator Frequency vs Temperature,, X Option
LM26420 30069649_nvs579.gif
Figure 17. RDSON Top Vs Temperature (WQFN-16 Package)
LM26420 30069691_nvs579.gif
Figure 19. RDSON Top Vs Temperature (TSSOP-20 Package)
LM26420 30069654_nvs579.gif
Figure 21. IQ (Quiescent Current Switching), X Option
LM26420 30069659.png
Figure 23. VFB vs Temperature
LM26420 30069680_nvs579.gif
Figure 25. Reverse Current Limit vs Temperature
LM26420 30069683.png
Figure 2. Efficiency Vs Load, Y Option
LM26420 30069685.png
Figure 4. Efficiency vs Load, Y Option
LM26420 30069687.png
Figure 6. Efficiency vs Load, Y Option
LM26420 30069689.png
Figure 8. Efficiency vs Load, Y Option
LM26420 30069642.png
Figure 10. Efficiency vs Load, Y Option
LM26420 30069645_nvs579.gif
VIN = 3 V VOUT = 1.8 V
Figure 12. Load Regulation (All Options)
LM26420 30069646_nvs579.gif
VOUT = 1.8 V IOUT = 1000 mA
Figure 14. Line Regulation - Y Option
LM26420 30069648.png
Figure 16. Oscillator Frequency vs Temperature, Y Option
LM26420 30069650_nvs579.gif
Figure 18. RDSON Bottom Vs Temperature
(WQFN-16 Package)
LM26420 30069692x_nvs579.gif
Figure 20. RDSON Bottom vs Temperature
(TSSOP-20 Package)
LM26420 30069655_nvs579.gif
Figure 22. IQ (Quiescent Current Switching), Y Option
LM26420 30069653_nvs579.gif
VIN = 5 V and 3.3 V
Figure 24. Current Limit vs Temperature
LM26420 30069698.png
Figure 26. Short Circuit Waveforms