ZHCSNR4B May   2021  – April 2022 TPS25946

PRODUCTION DATA  

  1. 特性
  2. 应用
  3. 说明
  4. Revision History
  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 Switching Characteristics
      1.      15
    8. 7.8 Typical Characteristics
  8. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Undervoltage Lockout (UVLO and UVP)
      2. 8.3.2 Overvoltage Lockout (OVLO)
      3. 8.3.3 Inrush Current, Overcurrent, and Short-Circuit Protection
        1. 8.3.3.1 Slew Rate (dVdt) and Inrush Current Control
        2. 8.3.3.2 Active Current Limiting
        3. 8.3.3.3 Short-Circuit Protection
      4. 8.3.4 Analog Load Current Monitor
      5. 8.3.5 Reverse Current Protection
      6. 8.3.6 Overtemperature Protection (OTP)
      7. 8.3.7 Fault Response and Indication (FLT)
      8. 8.3.8 Power Good Indication (PG)
      9. 8.3.9 Input Supply Good Indication (SPLYGD)
    4. 8.4 Device Functional Modes
  9. Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Single Device, Self-Controlled
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Device Selection
        2. 9.2.2.2 Setting Overvoltage Threshold
        3. 9.2.2.3 Setting Output Voltage Rise Time (tR)
        4. 9.2.2.4 Setting Power Good Assertion Threshold
        5. 9.2.2.5 Setting Overcurrent Threshold (ILIM)
        6. 9.2.2.6 Setting Overcurrent Blanking Interval (tITIMER)
        7. 9.2.2.7 Selecting External Bias Resistor (R5)
        8. 9.2.2.8 Selecting External Diode (D1)
      3. 9.2.3 Application Curve
  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. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Documentation
    2. 12.2 接收文档更新通知
    3. 12.3 支持资源
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 术语表
  13. 13Mechanical, Packaging, and Orderable 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

Layout Guidelines

  • For all applications, TI recommends a ceramic decoupling capacitor of 0.1 μF or greater between the IN terminal and GND terminal.
  • The optimal placement of the 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.
  • High current-carrying power-path connections must be as short as possible and must 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 with the shortest possible trace. The PCB ground must be a copper plane or island on the board. TI recommends to have a separate ground plane island for the eFuse. This plane doesn't carry any high currents and serves as a quiet ground reference for all the critical analog signals of the eFuse. The device ground plane must be connected to the system power ground plane using a star connection.
  • The IN and OUT pins are used for heat dissipation. Connect to as much copper area on top and bottom PCB layers using as possible. Adding thermal vias on the under the device further helps to minimize the voltage gradient across the IN and OUT pads and distribute current uniformly through the device, which improves the on-resistance and current sense accuracy.
  • Locate the following support components close to their connection pins:
    • RILM
    • CdVdT
    • CITIMER
    • Resistors for the EN/UVLO, OVLO and PGTH pins
  • Connect the other end of the component to the GND pin of the device with shortest trace length. The trace routing for the RILM, CITIMER and CdVdt components to the device must be as short as possible to reduce parasitic effects on the current limit , overcurrent blanking interval and soft start timing. TI recommends to keep parasitic capacitance on ILM pin below 50 pF to ensure stable operation. These traces must not have any coupling to switching signals on the board.
  • Because the bias current on ILM pin directly controls the overcurrent protection behavior of the device, the PCB routing of this node must be kept away from any noisy (switching) signals.
  • Protection devices such as TVS, snubbers, capacitors, or diodes must be placed physically close to the device they are intended to protect. These protection devices must be 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. TI also recommends to add a ceramic decoupling capacitor of 1 μF or greater between OUT and GND. These components must be physically close to the OUT pins. Care must be taken to minimize the loop area formed by the Schottky diode/bypass-capacitor connection, the OUT pin and the GND terminal of the IC.