ZHCSKM9F May   2011  – December 2019 LM5050-1 , LM5050-1-Q1

PRODUCTION DATA.  

  1. 特性
  2. 应用
  3. 说明
    1.     Device Images
      1.      完整应用
      2.      典型冗余电源配置
  4. 修订历史记录
  5. Pin Configuration and Functions
    1.     Pin Functions
  6. Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings: LM5050-1
    3. 6.3 ESD Ratings: LM5050-1-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 IN, GATE, and OUT Pins
      2. 7.3.2 VS Pin
      3. 7.3.3 OFF Pin
    4. 7.4 Device Functional Modes
      1. 7.4.1 ON/OFF Control Mode
      2. 7.4.2 External Power Supply Mode
  8. Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 MOSFET Selection
      2. 8.1.2 Short Circuit Failure of an Input Supply
    2. 8.2 Typical Applications
      1. 8.2.1 Typical Application With Input and Output Transient Protection
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Power Supply Components (R1 C1,) Selection
          2. 8.2.1.2.2 MOSFET (Q1) Selection
          3. 8.2.1.2.3 D1 and D2 Selection for Inductive Kick-Back Protection
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Using a Separate VS Supply for Low Vin Operation
      3. 8.2.3 ORing of Two Power Sources
      4. 8.2.4 Reverse Input Voltage Protection With IQ Reduction
      5. 8.2.5 Basic Application With Input Transient Protection
      6. 8.2.6 48-V Application With Reverse Input Voltage (VIN = –48 V) Protection
        1. 8.2.6.1 Application Curves
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11器件和文档支持
    1. 11.1 文档支持
      1. 11.1.1 相关文档
    2. 11.2 相关链接
    3. 11.3 社区资源
    4. 11.4 商标
    5. 11.5 静电放电警告
    6. 11.6 Glossary
  12. 12机械、封装和可订购信息

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

Short Circuit Failure of an Input Supply

An abrupt 0-Ω short circuit across the input supply will cause the highest possible reverse current to flow while the internal LM5050-1 control circuitry discharges the gate of the MOSFET. During this time, the reverse current is limited only by the RDS(ON) of the MOSFET, along with parasitic wiring resistances and inductances. Worst case instantaneous reverse current would be limited to:

Equation 1. ID(REV) = (VOUT - VIN) / RDS(ON)

The internal Reverse Comparator will react, and will start the process of discharging the Gate, when the reverse current reaches:

Equation 2. ID(REV) = VSD(REV) / RDS(ON)

When the MOSFET is finally switched off, the energy stored in the parasitic wiring inductances will be transferred to the rest of the circuit. As a result, the LM5050-1 IN pin will see a negative voltage spike while the OUT pin will see a positive voltage spike. The IN pin can be protected by diode clamping the pin to GND in the negative direction. The OUT pin can be protected with a TVS protection diode, a local bypass capacitor, or both. In low voltage applications, the MOSFET drainto- source breakdown voltage rating may be adequate to protect the OUT pin (that is, VIN + V(BR)DSS(MAX) < 75 V ), but most MOSFET data sheets do not ensure the maximum breakdown rating, so this method should be used with caution.

LM5050-1 LM5050-1-Q1 30104824.gifFigure 23. Reverse Recovery Current Generates Inductive Spikes at VIN and VOUT pins.