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

11.20 Sequencing (SS/TR)

Many of the common power supply sequencing methods can be implemented using the SS/TR, INH and PWRGD pins. The sequential method is illustrated in Figure 38 using two TPS84A20 devices. The PWRGD pin of the first device is coupled to the INH pin of the second device which enables the second power supply once the primary supply reaches regulation. Figure 39 shows sequential turnon waveforms of two TPS84A20 devices.

TPS84A20 slvsAW7_SequentialSeq.gifFigure 38. Sequencing Schematic
TPS84A20 waveformo_lvsa43.pngFigure 39. Sequencing Waveforms

Simultaneous power supply sequencing can be implemented by connecting the resistor network of R1 and R2 shown in Figure 40 to the output of the power supply that needs to be tracked or to another voltage reference source. The tracking voltage must exceed 750 mV before VOUT2 reaches its set-point voltage.Figure 41 shows simultaneous turnon waveforms of two TPS84A20 devices. Use and to calculate the values of R1 and R2.

TPS84A20 slvsAW7_SimultSeq.gifFigure 40. Simultaneous Tracking Schematic
TPS84A20 waveformp_lvsa43.pngFigure 41. Simultaneous Tracking Waveforms