ZHCSGK9B April   2017  – December 2017 TPS22971

PRODUCTION DATA.  

  1. 1 特性
  2. 2 应用
  3. 3 说明
    1.     Device Images
      1.      典型应用
  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 Switching Characteristics
    7. 6.7 Typical DC Characteristics
    8. 6.8 Typical AC Characteristics
  7. 7 Parameter Measurement Information
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 On and Off Control
      2. 8.3.2 Controlled Turn-On
      3. 8.3.3 Power Good (PG)
      4. 8.3.4 Quick Output Discharge (QOD)
    4. 8.4 Device Functional Modes
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Thermal Consideration
      2. 9.1.2 PG Pull Up Resistor
      3. 9.1.3 Power Sequencing
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Maximum Voltage Drop and On-Resistance
        2. 9.2.2.2 Managing Inrush Current
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12器件和文档支持
    1. 12.1 文档支持
      1. 12.1.1 相关文档
    2. 12.2 接收文档更新通知
    3. 12.3 社区资源
    4. 12.4 商标
    5. 12.5 静电放电警告
    6. 12.6 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

9.1.2 PG Pull Up Resistor

The PG output is an open drain signal which connects to a voltage source through a pull up resistor RPU. The PG signal can be used to drive the enable pins of downstream devices, EN. PG is active high, and its voltage is given by Equation 7.

Equation 7. TPS22971 tps22971x-equation-07.gif

where

  • VOUT is the voltage where PG is tied to
  • IPG,LK is the leakage current into PG pin
  • IEN,LK is the leakage current into the EN pin driven by PG
  • RPU is the pull up resistance

VPG needs to be higher than VIH,MIN of the EN pin to be treated as logic high. The maximum RPU is determined by Equation 8.

Equation 8. TPS22971 tps22971x-equation-08.gif

When PG is disabled, with 1 mA current into PG pin (IPG = 1 mA), VPG.OL is less than 0.2 V and treated as logic low as long as VIL,MAX of the EN pin is greater than 0.2 V. The minimum RPU is determined by Equation 9.

Equation 9. TPS22971 tps22971x-equation-09.gif

RPU can be chosen within the range defined by RPU,MIN and RPU,MAX. RPU = 10 kΩ is used for characterization.