JAJSM84B december   2022  – july 2023 LM74900-Q1 , LM74910-Q1

PRODUCTION DATA  

  1.   1
  2. 特長
  3. アプリケーション
  4. 概要
  5. Revision History
  6. Device Comparison Table
  7. Pin Configuration and Functions
  8. 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 スイッチング特性
    7. 7.7 Typical Characteristics
  9. Parameter Measurement Information
  10. Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Charge Pump
      2. 9.3.2 Dual Gate Control (DGATE, HGATE)
        1. 9.3.2.1 Reverse Battery Protection (A, C, DGATE)
        2. 9.3.2.2 Load Disconnect Switch Control (HGATE, OUT)
      3. 9.3.3 Overcurrent Protection (CS+, CS-, ILIM, IMON, TMR)
        1. 9.3.3.1 Pulse Overload Protection, Circuit Breaker
        2. 9.3.3.2 Overcurrent Protection With Latch-Off
        3. 9.3.3.3 Short Circuit Protection (ISCP)
        4. 9.3.3.4 Analog Current Monitor Output (IMON)
      4. 9.3.4 Undervoltage Protection, Overvoltage Protection, and Battery Voltage Sensing (UVLO, OV, SW)
      5. 9.3.5 Low IQ SLEEP Mode (SLEEP)
      6. 9.3.6 Ultra Low IQ Shutdown (EN)
  11. 10Applications and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical 12-V Reverse Battery Protection Application
      1. 10.2.1 Design Requirements for 12-V Battery Protection
      2. 10.2.2 Automotive Reverse Battery Protection
        1. 10.2.2.1 Input Transient Protection: ISO 7637-2 Pulse 1
        2. 10.2.2.2 AC Super Imposed Input Rectification: ISO 16750-2 and LV124 E-06
        3. 10.2.2.3 Input Micro-Short Protection: LV124 E-10
      3. 10.2.3 Detailed Design Procedure
        1. 10.2.3.1 Design Considerations
        2. 10.2.3.2 Charge Pump Capacitance VCAP
        3. 10.2.3.3 Input and Output Capacitance
        4. 10.2.3.4 Hold-Up Capacitance
        5. 10.2.3.5 Selection of Current Sense Resistor, RSNS
        6. 10.2.3.6 Selection of Scaling Resistor (RSET) and Short-Circuit Protection Setting Resistor (RSCP)
        7. 10.2.3.7 Overcurrent Limit (ILIM), Circuit Breaker Timer (TMR), and Current Monitoring Output (IMON) Selection
        8. 10.2.3.8 Overvoltage Protection and Battery Monitor
      4. 10.2.4 MOSFET Selection: Blocking MOSFET Q1
      5. 10.2.5 MOSFET Selection: Hot-Swap MOSFET Q2
      6. 10.2.6 TVS Selection
      7. 10.2.7 Application Curves
    3. 10.3 Addressing Automotive Input Reverse Battery Protection Topologies With LM749x0-Q1
    4. 10.4 Power Supply Recommendations
      1. 10.4.1 Transient Protection
      2. 10.4.2 TVS Selection for 12-V Battery Systems
    5. 10.5 Layout
      1. 10.5.1 Layout Guidelines
  12. 11Device and Documentation Support
    1. 11.1 ドキュメントの更新通知を受け取る方法
    2. 11.2 サポート・リソース
    3. 11.3 Trademarks
    4. 11.4 静電気放電に関する注意事項
    5. 11.5 用語集
  13. 12Mechanical, Packaging, and Orderable Information

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

Input Transient Protection: ISO 7637-2 Pulse 1

ISO 7637-2 Pulse 1 specifies negative transient immunity of electronic modules connected in parallel with an inductive load when the battery is disconnected. A typical pulse 1 specified in ISO 7637-2 starts with battery disconnection where supply voltage collapses to 0 V followed by –150 V 2 ms applied with a source impedance of 10 Ω at a slew rate of 1 µs on the supply input. LM749x0-Q1 blocks reverse current and prevents the output voltage from swinging negative, protecting the rest of the electronic circuits from damage due to negative transient voltage. MOSFET Q1 is quickly turned off within 0.5 µs by fast reverse comparator of LM749x0-Q1. A single bi-directional TVS is required at the input to clamp the negative transient pulse within the operating maximum voltage across cathode to anode of 85 V and does not violate the MOSFET Q1 drain-source breakdown voltage rating.

ISO 7637-2 Pulse 1 performance of LM749x0-Q1 is shown in Figure 10-2.

GUID-20221214-SS0I-FDKX-LTN8-1WR094LVKPXF-low.pngFigure 10-2 ISO 7637-2 Pulse 1