SBVS446A August   2023  – January 2024 TPS7A53B

PRODUCTION DATA  

  1.   1
  2. Features
  3. Applications
  4. Description
  5. Pin Configuration and Functions
  6. Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Typical Characteristics
  7. Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Voltage Regulation Features
        1. 6.3.1.1 DC Regulation
        2. 6.3.1.2 AC and Transient Response
      2. 6.3.2 System Start-Up Features
        1. 6.3.2.1 Programmable Soft-Start (NR/SS Pin)
        2. 6.3.2.2 Internal Sequencing
          1. 6.3.2.2.1 Enable (EN)
          2. 6.3.2.2.2 Undervoltage Lockout (UVLO) Control
          3. 6.3.2.2.3 Active Discharge
        3. 6.3.2.3 Power-Good Output (PG)
      3. 6.3.3 Internal Protection Features
        1. 6.3.3.1 Foldback Current Limit (ICL)
        2. 6.3.3.2 Thermal Protection (Tsd)
    4. 6.4 Device Functional Modes
      1. 6.4.1 Regulation
      2. 6.4.2 Disabled
      3. 6.4.3 Current Limit Operation
  8. Application and Implementation
    1. 7.1 Application Information
      1. 7.1.1  Recommended Capacitor Types
        1. 7.1.1.1 Input and Output Capacitor Requirements (CIN and COUT)
        2. 7.1.1.2 Noise-Reduction and Soft-Start Capacitor (CNR/SS)
        3. 7.1.1.3 Feed-Forward Capacitor (CFF)
      2. 7.1.2  Soft-Start and Inrush Current
      3. 7.1.3  Optimizing Noise and PSRR
      4. 7.1.4  Charge Pump Noise
      5. 7.1.5  Current Sharing
      6. 7.1.6  Adjustable Operation
      7. 7.1.7  Power-Good Operation
      8. 7.1.8  Undervoltage Lockout (UVLO) Operation
      9. 7.1.9  Dropout Voltage (VDO)
      10. 7.1.10 Device Behavior During Transition From Dropout Into Regulation
      11. 7.1.11 Load Transient Response
      12. 7.1.12 Reverse Current Protection Considerations
      13. 7.1.13 Power Dissipation (PD)
      14. 7.1.14 Estimating Junction Temperature
      15. 7.1.15 TPS7A53EVM Thermal Analysis
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
      3. 7.2.3 Application Curves
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
        1. 7.4.1.1 Board Layout
      2. 7.4.2 Layout Example
  9. Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Device Nomenclature
    2. 8.2 Documentation Support
      1. 8.2.1 Related Documentation
    3. 8.3 Receiving Notification of Documentation Updates
    4. 8.4 Support Resources
    5. 8.5 Trademarks
    6. 8.6 Electrostatic Discharge Caution
    7. 8.7 Glossary
  10. Revision History
  11. 10Mechanical, Packaging, and Orderable Information

Package Options

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

Detailed Design Procedure

At 3.0A and given a VBIAS of 5.0V, the TPS7A53B has a 110mV maximum dropout over temperature, Thus, a 300mV headroom is sufficient for operation over both input and output voltage accuracy. At full load and high temperature on some devices, the TPS7A53B can enter dropout if both the input and output supply are beyond the edges of the respective accuracy specification.

For a 0.9V output, use external adjustable resistors. See the resistor values listed in Table 7-2 for choosing resistors for a 0.9V output.

Input and output capacitors are selected in accordance with the Recommended Capacitor Types section. Ceramic capacitances of 47µF for the input and one 47µF capacitor in parallel with two 10µF capacitors for the output are selected.

To satisfy the required start-up time and still maintain low noise performance, a 100nF CNR/SS is selected. Equation 9 calculates this value.

Equation 9. tSS = (VNR/SS × CNR/SS) / INR/SS

At the 3.0A maximum load, the internal power dissipation is 0.9W and corresponds to a 61.8°C junction temperature rise for the RPS package on a standard JEDEC board. With a 55°C maximum ambient temperature, the junction temperature is at 116.8°C. To further minimize noise, a feed-forward capacitance (CFF) of 10nF is selected.