SBVS398A December   2021  – September 2022 TPS7A21

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1 Absolute Maximum Ratings
    2. 6.2 ESD Ratings
    3. 6.3 Recommended 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 Smart Enable (EN)
      2. 7.3.2 Low Output Noise
      3. 7.3.3 Active Discharge
      4. 7.3.4 Dropout Voltage
      5. 7.3.5 Foldback Current Limit
      6. 7.3.6 Undervoltage Lockout
      7. 7.3.7 Thermal Overload Protection (TSD)
    4. 7.4 Device Functional Modes
      1. 7.4.1 Device Functional Mode Comparison
      2. 7.4.2 Normal Operation
      3. 7.4.3 Dropout Operation
      4. 7.4.4 Disabled
  8. 8 Applications and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Recommended Capacitor Types
      2. 8.1.2 Input and Output Capacitor Requirements
      3. 8.1.3 Load Transient Response
      4. 8.1.4 Undervoltage Lockout (UVLO) Operation
      5. 8.1.5 Power Dissipation (PD)
      6. 8.1.6 Estimating Junction Temperature
      7. 8.1.7 Recommended Area For Continuous Operation
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Power Dissipation and Device Operation
      3. 8.2.3 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
        1. 8.4.1.1 DSBGA Mounting
        2. 8.4.1.2 DSBGA Light Sensitivity
      2. 8.4.2 Layout Example
  9. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Device Nomenclature
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
    3. 9.3 Receiving Notification of Documentation Updates
    4. 9.4 Support Resources
    5. 9.5 Trademarks
    6. 9.6 Electrostatic Discharge Caution
    7. 9.7 Glossary
  10. 10Mechanical, Packaging, and Orderable Information
    1. 10.1 Mechanical Data

8.1.2 Input and Output Capacitor Requirements

Although the LDO is stable without an input capacitor, good design practice is to connect a capacitor from IN to GND, with a value at least equal to the nominal value specified in the Section 6.3 table. The input capacitor counteracts reactive input sources and improves transient response, input ripple, and PSRR, and is recommended if the source impedance is greater than 0.5 Ω. When the source resistance and inductance are sufficiently high, the overall system can be susceptible to instability (including ringing and sustained oscillation) and other performance degradation if there is insufficient capacitance between IN and GND. A capacitor with a value greater than the minimum may be necessary if there are large fast-rise-time load or line transients or if the LDO is located more than a few centimeters from the input power source.

An output capacitor of an appropriate value helps ensure stability and improve dynamic performance. Use an output capacitor within the range specified in the Section 6.3 table.