SLVSDN3 June   2017 TPS82140

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Typical Application Schematic spacespace
      2.      Efficiency vs Output Current, VIN=12V space
  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 Recommend 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 PWM and PSM Operation
      2. 7.3.2 Low Dropout Operation (100% Duty Cycle)
      3. 7.3.3 Switch Current Limit
      4. 7.3.4 Undervoltage Lockout
      5. 7.3.5 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Enable and Disable (EN)
      2. 7.4.2 Soft Startup (SS/TR)
      3. 7.4.3 Voltage Tracking (SS/TR)
      4. 7.4.4 Power Good Output (PG)
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 1.8-V Output Application
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Custom Design with WEBENCH® Tools
          2. 8.2.1.2.2 Setting the Output Voltage
          3. 8.2.1.2.3 Input and Output Capacitor Selection
          4. 8.2.1.2.4 Soft Startup Capacitor Selection
        3. 8.2.1.3 Application Performance Curves
    3. 8.3 System Examples
      1. 8.3.1 Inverting Power Supply
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Thermal Consideration
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
      2. 11.1.2 Development Support
        1. 11.1.2.1 Custom Design With WEBENCH® Tools
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Community Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information
    1. 12.1 Package Materials Information
      1. 12.1.1 Tape and Reel Information

Package Options

Mechanical Data (Package|Pins)
  • SIL|8
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7.4.3 Voltage Tracking (SS/TR)

The SS/TR pin is externally driven by another voltage source to achieve output voltage tracking. The application circuit is shown in Figure 4.

TPS82140 TPS82140_Voltagetracking.gifFigure 4. Output Voltage Tracking

When the SS/TR pin voltage is between 50 mV and 1.2 V, the VOUT2 tracks the VOUT1 as described in Equation 5.

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Equation 5. TPS82140 EQ_Voltagetracking.gif

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When the SS/TR pin voltage is above 1.2 V, the voltage tracking is disabled and the FB pin voltage is regulated at 0.8 V. For decreasing SS/TR pin voltage, the device doesn't sink current from the output. So the resulting decreases of the output voltage may be slower than the SS/TR pin voltage if the load is light. When driving the SS/TR pin with an external voltage, do not exceed the voltage rating of the SS/TR pin which is VIN+0.3V.

Details about tracking and sequencing circuits are found in SLVA470.