ZHCSBM9C SEPTEMBER   2013  – June 2018 TPS53513

PRODUCTION DATA.  

  1. 1 特性
  2. 2 应用
  3. 3 说明
    1.     Device Images
      1.      简化原理图
      2.      效率
  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
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  5-V LDO and VREG Start-Up
      2. 7.3.2  Enable, Soft Start, and Mode Selection
      3. 7.3.3  Frequency Selection
      4. 7.3.4  D-CAP3 Control and Mode Selection
        1. 7.3.4.1 D-CAP3 Mode
        2. 7.3.4.2 Sample and Hold Circuitry
        3. 7.3.4.3 Adaptive Zero-Crossing
      5. 7.3.5  Power-Good
      6. 7.3.6  Current Sense and Overcurrent Protection
      7. 7.3.7  Overvoltage and Undervoltage Protection
      8. 7.3.8  Out-Of-Bounds Operation
      9. 7.3.9  UVLO Protection
      10. 7.3.10 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Auto-Skip Eco-mode Light Load Operation
      2. 7.4.2 Forced Continuous-Conduction Mode
  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 Choose the Switching Frequency
        2. 8.2.2.2 Choose the Operation Mode
        3. 8.2.2.3 Choose the Inductor
        4. 8.2.2.4 Choose the Output Capacitor
        5. 8.2.2.5 Determine the Value of R1 and R2
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Thermal Performance
  11. 11器件和文档支持
    1. 11.1 文档支持
      1. 11.1.1 使用 WEBENCH® 工具创建定制设计方案
    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 社区资源
    5. 11.5 商标
    6. 11.6 静电放电警告
    7. 11.7 术语表
  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

7.4.1 Auto-Skip Eco-mode Light Load Operation

While the MODE pin is pulled to GND directly or through 150-kΩ resistor, the TPS53513 device automatically reduces the switching frequency at light-load conditions to maintain high efficiency. This section describes the operation in detail.

As the output current decreases from heavy load condition, the inductor current also decreases until the rippled valley of the inductor current touches zero level. Zero level is the boundary between the continuous-conduction and discontinuous-conduction modes. The synchronous MOSFET turns off when this zero inductor current is detected. As the load current decreases further, the converter runs into discontinuous-conduction mode (DCM). The on-time is maintained to a level approximately the same as during continuous-conduction mode operation so that discharging the output capacitor with a smaller load current to the level of the reference voltage requires more time. The transition point to the light-load operation IO(LL) (for example: the threshold between continuous- and discontinuous-conduction mode) is calculated as shown in Equation 6.

Equation 6. TPS53513 q_ioutll_slusbn5.gif

where

  • fSW is the PWM switching frequency

Using only ceramic capacitors is recommended for Auto-skip mode.