ZHCS535M February   2013  – October 2020 LM22679 , LM22679-Q1

PRODUCTION DATA  

  1. 特性
  2. 应用
  3. 说明
  4. Revision History
  5. Pin Configuration and Functions
    1.     Pin Functions
  6. Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 Handling Ratings: LM22679
    3. 6.3 Handling Ratings: LM22679-Q1
    4. 6.4 Recommended Operating Conditions
    5. 6.5 Thermal Information
    6. 6.6 Electrical Characteristics
    7. 6.7 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 UVLO
      2. 7.3.2 Soft-Start
      3. 7.3.3 Bootstrap Supply
      4. 7.3.4 Internal Compensation
    4. 7.4 Device Functional Modes
      1. 7.4.1 Shutdown Mode
      2. 7.4.2 Active Mode
      3. 7.4.3 Current Limit
      4. 7.4.4 Current Limit Adjustment
      5. 7.4.5 Thermal Protection
      6. 7.4.6 Duty-Cycle Limits
  8. Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Output Voltage Divider Selection
      2. 8.1.2 Power Diode
    2. 8.2 Typical Application
      1. 8.2.1 Typical Buck Regulator Application
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 External Components
          2. 8.2.1.2.2 Inductor
          3. 8.2.1.2.3 Input Capacitor
          4. 8.2.1.2.4 Output Capacitor
          5. 8.2.1.2.5 Bootstrap Capacitor
        3. 8.2.1.3 Application Curve
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Thermal Considerations
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 支持资源
    3. 11.3 接收文档更新通知
    4. 11.4 Trademarks
    5. 11.5 术语表
    6. 11.6 静电放电警告

封装选项

机械数据 (封装 | 引脚)
散热焊盘机械数据 (封装 | 引脚)
订购信息
Output Capacitor

The output capacitor is responsible for filtering the output voltage and supplying load current during transients. Capacitor selection depends on application conditions as well as ripple and transient requirements. Best performance is achieved with a parallel combination of ceramic capacitors and a low ESR SP™ or POSCAP™ types. Very low ESR capacitors such as ceramics reduce the output ripple and noise spikes, while higher value electrolytics or polymers provide large bulk capacitance to supply transients. Assuming very low ESR, Equation 15 gives an approximation to the output voltage ripple:

Equation 15. GUID-4414D500-9D6C-4F8B-971B-A4BB425E4F92-low.gif

Typically, a total value of 100 µF or greater is recommended for output capacitance.

In applications with Vout less than 3.3 V, it is critical that low ESR output capacitors are selected. This will limit potential output voltage overshoots as the input voltage falls below the device normal operating range.