SLVSBC6C March   2013  – December 2019 TPS84A20

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Application
  4. 4 Revision History
  5. 5 Ordering Information
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 Recommended Operating Conditions
    3. 6.3 Package Specifications
    4. 6.4 Electrical Characteristics
    5. 6.5 Thermal Information
  7. 7 Device Information
    1. 7.1      Functional Block Diagram
    2. Table 1. Pin Descriptions
  8. 8 Typical Characteristics (PVIN = VIN = 12 V)
  9. 9 Typical Characteristics (PVIN = VIN = 5 V)
  10. 10Typical Characteristics (PVIN = 3.3 V, VIN = 5 V)
  11. 11Application Information
    1. 11.1  Adjusting the Output Voltage
    2. 11.2  Capacitor Recommendations for the TPS84A20 Power Supply
      1. 11.2.1 Capacitor Technologies
        1. 11.2.1.1 Electrolytic, Polymer-Electrolytic Capacitors
        2. 11.2.1.2 Ceramic Capacitors
        3. 11.2.1.3 Tantalum, Polymer-Tantalum Capacitors
      2. 11.2.2 Input Capacitor
      3. 11.2.3 Output Capacitor
    3. 11.3  Transient Response
    4. 11.4  Transient Waveforms
    5. 11.5  Application Schematics
    6. 11.6  VIN and PVIN Input Voltage
    7. 11.7  3.3 V PVIN Operation
    8. 11.8  Power Good (PWRGD)
    9. 11.9  Light Load Efficiency (LLE)
    10. 11.10 SYNC_OUT
    11. 11.11 Parallel Operation
    12. 11.12 Power-Up Characteristics
    13. 11.13 Pre-Biased Start-Up
    14. 11.14 Remote Sense
    15. 11.15 Thermal Shutdown
    16. 11.16 Output On/Off Inhibit (INH)
    17. 11.17 Slow Start (SS/TR)
    18. 11.18 Overcurrent Protection
    19. 11.19 Synchronization (CLK)
    20. 11.20 Sequencing (SS/TR)
    21. 11.21 Programmable Undervoltage Lockout (UVLO)
    22. 11.22 Layout Considerations
    23. 11.23 EMI
  12. 12Device and Documentation Support
    1. 12.1 Receiving Notification of Documentation Updates
    2. 12.2 Support Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information
    1. 13.1 Tape and Reel Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • RVQ|42
Thermal pad, mechanical data (Package|Pins)
Orderable Information

11.16 Output On/Off Inhibit (INH)

The INH pin provides electrical on/off control of the device. Once the INH pin voltage exceeds the threshold voltage, the device starts operation. If the INH pin voltage is pulled below the threshold voltage, the regulator stops switching and enters low quiescent current state.

The INH pin has an internal pullup current source, allowing the user to float the INH pin for enabling the device. If an application requires controlling the INH pin, use an open drain/collector device, or a suitable logic gate to interface with the pin.

Figure 29 shows the typical application of the inhibit function. The Inhibit control has its own internal pullup to VIN potential. An open-collector or open-drain device is recommended to control this input.

Turning Q1 on applies a low voltage to the inhibit control (INH) pin and disables the output of the supply, shown in Figure 30. If Q1 is turned off, the supply executes a soft-start power-up sequence, as shown in Figure 31. A regulated output voltage is produced within 2 ms. The waveforms were measured with a 5-A constant current load.

TPS84A20 slvsBC6_INHcontrol.gifFigure 29. Typical Inhibit Control
TPS84A20 inh_shutdown.pngFigure 30. Inhibit Turn-Off
TPS84A20 inh_release.pngFigure 31. Inhibit Turn-On