ZHCSE39A August   2015  – August 2015

PRODUCTION DATA.  

  1. 特性
  2. 应用
  3. 说明
  4. 修订历史记录
  5. Device Comparison Table
  6. Pin Configuration and Functions
  7. 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 Timing Requirements
    7. 7.7 Typical Characteristics
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 GND
      2. 8.3.2 VIN
      3. 8.3.3 dV/dT
      4. 8.3.4 BFET
      5. 8.3.5 EN/UVLO
      6. 8.3.6 ILIM
    4. 8.4 Device Functional Modes
  9. Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Applications
      1. 9.2.1 Simple 3.7-A eFuse Protection for Set Top Boxes
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Step by Step Design Procedure
          2. 9.2.1.2.2 Programming the Current-Limit Threshold: RILIM Selection
          3. 9.2.1.2.3 Undervoltage Lockout Set Point
          4. 9.2.1.2.4 Setting Output Voltage Ramp Time (TdVdT)
            1. 9.2.1.2.4.1 Case 1: Start-Up without Load: Only Output Capacitance COUT Draws Current During Start-Up
            2. 9.2.1.2.4.2 Case 2: Start-Up with Load: Output Capacitance COUT and Load Draws Current During Start-Up
          5. 9.2.1.2.5 Support Component Selection - CVIN
        3. 9.2.1.3 Application Curves
      2. 9.2.2 Inrush and Reverse Current Protection for Hold-Up Capacitor Application (for example, SSD)
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
          1. 9.2.2.2.1 Programming the Current-Limit Threshold: RILIM Selection
          2. 9.2.2.2.2 Undervoltage Lockout Set Point
          3. 9.2.2.2.3 Setting Output Voltage Ramp Time (TdVdT)
          4. 9.2.2.2.4 Support Component Selection - CVIN
        3. 9.2.2.3 Application Curves
  10. 10Power Supply Recommendations
    1. 10.1 Transient Protection
    2. 10.2 Output Short-Circuit Measurements
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12器件和文档支持
    1. 12.1 器件支持
      1. 12.1.1 Third-Party Products Disclaimer
    2. 12.2 文档支持
      1. 12.2.1 相关文档
    3. 12.3 相关链接
    4. 12.4 社区资源
    5. 12.5 商标
    6. 12.6 静电放电警告
    7. 12.7 Glossary
  13. 13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

11 Layout

11.1 Layout Guidelines

  • For all applications, a 0.01-µF or greater ceramic decoupling capacitor is recommended between IN terminal and GND. For hot-plug applications, where input power path inductance is negligible, this capacitor can be eliminated/minimized.
  • The optimum placement of decoupling capacitor is closest to the IN and GND terminals of the device. Care must be taken to minimize the loop area formed by the bypass-capacitor connection, the IN terminal, and the GND terminal of the IC. See Figure 47 for a PCB layout example.
  • High current carrying power path connections should be as short as possible and should be sized to carry at least twice the full-load current.
  • The GND terminal must be tied to the PCB ground plane at the terminal of the IC. The PCB ground should be a copper plane or island on the board.
  • Locate all support components: RILIM, CdVdT and resistors for EN/UVLO, close to their connection pin. Connect the other end of the component to the GND pin of the device with shortest trace length. The trace routing for the RILIM and CdVdT components to the device should be as short as possible to reduce parasitic effects on the current limit and soft start timing. These traces should not have any coupling to switching signals on the board.
  • Protection devices such as TVS, snubbers, capacitors, or diodes should be placed physically close to the device they are intended to protect, and routed with short traces to reduce inductance. For example, a protection Schottky diode is recommended to address negative transients due to switching of inductive loads, and it should be physically close to the OUT pins.
  • Obtaining acceptable performance with alternate layout schemes is possible; however this layout has been shown to produce good results and is intended as a guideline.

11.2 Layout Example

TPS259230 TPS259231 Layout_Ex2_lvscu8.gif Figure 47. Layout Example