SNVSBI8E august   2020  – august 2023 TPS38-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Revision History
  6. 5 Device Comparison
  7. 6 Pin Configuration and Functions
  8. 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 Timing Diagrams
    8. 7.8 Typical Characteristics
  9. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Input Voltage (VDD)
        1. 8.3.1.1 Undervoltage Lockout (VPOR < VDD < UVLO)
        2. 8.3.1.2 Power-On Reset (VDD < VPOR )
      2. 8.3.2 SENSE
        1. 8.3.2.1 SENSE Hysteresis
      3. 8.3.3 Output Logic Configurations
        1. 8.3.3.1 Open-Drain
        2. 8.3.3.2 Push-Pull
        3. 8.3.3.3 Active-High (RESET)
        4. 8.3.3.4 Active-Low (RESET)
      4. 8.3.4 User-Programmable Reset Time Delay
        1. 8.3.4.1 Reset Time Delay Configuration
      5. 8.3.5 User-Programmable Sense Delay
        1. 8.3.5.1 Sense Time Delay Configuration
      6. 8.3.6 Manual RESET (CTR1 / MR) and (CTR2 / MR) Input
      7. 8.3.7 Adjustable Voltage Thresholds
    4. 8.4 Device Functional Modes
  10. 9 Application and Implementation
    1. 9.1 Adjustable Voltage Thresholds
    2. 9.2 Application Information
    3. 9.3 Typical Application
      1. 9.3.1 Design 1: Automotive Off-Battery Monitoring
        1. 9.3.1.1 Design Requirements
        2. 9.3.1.2 Detailed Design Procedure
        3. 9.3.1.3 Application Curves
    4. 9.4 Power Supply Recommendations
      1. 9.4.1 Power Dissipation and Device Operation
    5. 9.5 Layout
      1. 9.5.1 Layout Guidelines
      2. 9.5.2 Layout Example
      3. 9.5.3 Creepage Distance
  11. 10Device and Documentation Support
    1. 10.1 Device Nomenclature
    2. 10.2 Receiving Notification of Documentation Updates
    3. 10.3 Support Resources
    4. 10.4 Trademarks
    5. 10.5 Electrostatic Discharge Caution
    6. 10.6 Glossary

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

9.4.1 Power Dissipation and Device Operation

The permissible power dissipation for any package is a measure of the capability of the device to pass heat from the power source, the junctions of the IC, to the ultimate heat sink, the ambient environment. Thus, the power dissipation is dependent on the ambient temperature and the thermal resistance across the various interfaces between the die junction and ambient air.

The maximum continuous allowable power dissipation for the device in a given package can be calculated using Equation 17:

Equation 17. PD-MAX = ((TJ-MAX – TA) / RθJA)

The actual power being dissipated in the device can be represented by Equation 18:

Equation 18. PD = VDD × IDD+pRESET

pRESET is calculated by Equation 19 or Equation 20

Equation 19. pRESET (PUSHPULL) = VDD - VRESET x IRESET
Equation 20. pRESET (OPEN-DRAIN) = VRESET x IRESET

Equation 17 and Equation 18 establish the relationship between the maximum power dissipation allowed due to thermal consideration, the voltage drop across the device, and the continuous current capability of the device. These two equations should be used to determine the optimum operating conditions for the device in the application.

In applications where lower power dissipation (PD) and/or excellent package thermal resistance (RθJA) is present, the maximum ambient temperature (TA-MAX) may be increased.

In applications where high power dissipation and/or poor package thermal resistance is present, the maximum ambient temperature (TA-MAX) may have to be de-rated. TA-MAX is dependent on the maximum operating junction temperature (TJ-MAX-OP = 125°C), the maximum allowable power dissipation in the device package in the application (PD-MAX), and the junction-to ambient thermal resistance of the part/package in the application (RθJA), as given by Equation 21:

Equation 21. TA-MAX = (TJ-MAX-OP – (RθJA × PD-MAX))