ZHCSBC7E JULY   2013  – December 2019 LMZ31710

PRODUCTION DATA.  

  1. 1 特性
  2. 2 应用
  3. 3 说明
    1.     Device Images
      1.      简化应用
  4. 4 修订历史记录
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended Operating Conditions
    4. 6.4 Thermal Information
    5. 6.5 Electrical Characteristics
    6. 6.6 Typical Characteristics (PVIN = VIN = 12 V)
    7. 6.7 Typical Characteristics (PVIN = VIN = 5 V)
    8. 6.8 Typical Characteristics (PVIN = 3.3 V, VIN = 5 V)
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  VIN and PVIN Input Voltage
      2. 7.3.2  3.3-V PVIN Operation
      3. 7.3.3  Adjusting the Output Voltage (0.6 V to 5.5 V)
      4. 7.3.4  Capacitor Recommendations For the LMZ31710 Power Supply
        1. 7.3.4.1 Capacitor Technologies
          1. 7.3.4.1.1 Electrolytic, Polymer-Electrolytic Capacitors
          2. 7.3.4.1.2 Ceramic Capacitors
          3. 7.3.4.1.3 Tantalum, Polymer-Tantalum Capacitors
        2. 7.3.4.2 Input Capacitor
        3. 7.3.4.3 Output Capacitor
      5. 7.3.5  Transient Response
        1. 7.3.5.1 Transient Response Waveforms
      6. 7.3.6  Power Good (PWRGD)
      7. 7.3.7  Light Load Efficiency (LLE)
      8. 7.3.8  SYNC_OUT
      9. 7.3.9  Parallel Operation
      10. 7.3.10 Power-Up Characteristics
      11. 7.3.11 Pre-Biased Start-Up
      12. 7.3.12 Remote Sense
      13. 7.3.13 Thermal Shutdown
      14. 7.3.14 Output On/Off Inhibit (INH)
      15. 7.3.15 Slow Start (SS/TR)
      16. 7.3.16 Overcurrent Protection
      17. 7.3.17 Synchronization (CLK)
      18. 7.3.18 Sequencing (SS/TR)
    4. 7.4 Device Functional Modes
      1. 7.4.1 Programmable Undervoltage Lockout (UVLO)
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Custom Design With WEBENCH® Tools
        2. 8.2.2.2 Setting The Output Voltage
        3. 8.2.2.3 Setting the Switching Frequency
        4. 8.2.2.4 Input Capacitance
        5. 8.2.2.5 Output Capacitance
    3. 8.3 Additional Application Schematics
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Considerations
    2. 10.2 Layout Examples
      1. 10.2.1 EMI
  11. 11器件和文档支持
    1. 11.1 器件支持
      1. 11.1.1 开发支持
        1. 11.1.1.1 使用 WEBENCH® 工具创建定制设计
      2. 11.1.2 第三方产品免责声明
    2. 11.2 文档支持
      1. 11.2.1 相关文档
    3. 11.3 接收文档更新通知
    4. 11.4 支持资源
    5. 11.5 商标
    6. 11.6 静电放电警告
    7. 11.7 Glossary
  12. 12机械、封装和可订购信息
    1. 12.1 Tape and Reel Information

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

7.3.16 Overcurrent Protection

For protection against load faults, the LMZ31710 incorporates output overcurrent protection. The overcurrent protection mode can be selected using the OCP_SEL pin. Leaving the OCP_SEL pin open selects hiccup mode and connecting it to AGND selects cycle-by-cycle mode. In hiccup mode, applying a load that exceeds the overcurrent threshold of the regulator causes the regulated output to shut down. Following shutdown, the module periodically attempts to recover by initiating a soft-start power-up as shown in Figure 30. This is described as a hiccup mode of operation, whereby the module continues in a cycle of successive shutdown and power up until the load fault is removed. During this period, the average current flowing into the fault is significantly reduced which reduces power dissipation. Once the fault is removed, the module automatically recovers and returns to normal operation as shown in Figure 31.

In cycle-by-cycle mode, applying a load that exceeds the regulator's overcurrent threshold limits the output current and reduces the output voltage as shown in Figure 32. During this period, the current flowing into the fault remains high causing the power dissipation to stay high as well. Once the overcurrent condition is removed, the output voltage returns to the set-point voltage as shown in Figure 33.

LMZ31710 hiccup.pngFigure 30. Overcurrent Limiting (Hiccup)
LMZ31710 cycle_begin.pngFigure 32. Overcurrent Limiting (Cycle-By-Cycle)
LMZ31710 hiccup_release.pngFigure 31. Removal Of Overcurrent (Hiccup)
LMZ31710 cycle_end.pngFigure 33. Removal Of Overcurrent (Cycle-By-Cycle)