SLVSDK7C April   2017  – February 2020 TPS22971

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Typical Application
  4. 4 Revision History
  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. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Documentation
    2. 12.2 Receiving Notification of Documentation Updates
    3. 12.3 Community Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

8.3.3 Power Good (PG)

The TPS22971 has a power good (PG) output signal to indicate the gate of the pass FET is driven high and the switch is fully on (full load ready). The signal is an active high and open drain output which can be connected to a voltage source through an external pull up resistor, RPU. This voltage source can be VOUT from the TPS22971 or another external voltage. Equation 4 and Equation 5 show the approximate equation for the relationship between CT setting, VIN and PG Turn-On time (tPG,ON):

Equation 4. TPS22971 tps22971x-equation-04.gif
Equation 5. TPS22971 tps22971x-equation-05.gif

where

  • tPG,ON is the PG Turn-On time (in µs)
  • VIN is the input voltage (in V)
  • CT is the capacitance value on the CT pin (in pF)