SLVS351Q September   2002  – June 2025 TPS796

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 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. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagrams
    3. 6.3 Feature Description
      1. 6.3.1 Active Discharge (New Chip)
      2. 6.3.2 Shutdown
      3. 6.3.3 Start-Up
      4. 6.3.4 Undervoltage Lockout (UVLO)
      5. 6.3.5 Regulator Protection
        1. 6.3.5.1 Current Limit
        2. 6.3.5.2 Thermal Shutdown
    4. 6.4 Device Functional Modes
      1. 6.4.1 Normal Operation
      2. 6.4.2 Dropout Operation
      3. 6.4.3 Disabled
  8. 7 Application and Implementation
    1. 7.1 Application Information
      1. 7.1.1 Recommended Capacitor Types
      2. 7.1.2 Input and Output Capacitor Requirements
      3. 7.1.3 Feed-forward Capacitor (CFF)
      4. 7.1.4 Adjustable Configuration
      5. 7.1.5 Load Transient Response
      6. 7.1.6 Dropout Voltage
        1. 7.1.6.1 Exiting Dropout
      7. 7.1.7 Noise Reduction Pin (legacy chip)
      8. 7.1.8 Power Dissipation (PD)
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
      3. 7.2.3 Application Curves
      4. 7.2.4 Best Design Practices
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
        1. 7.4.1.1 Board Layout Recommendation to Improve PSRR and Noise Performance
        2. 7.4.1.2 Regulator Mounting
        3. 7.4.1.3 Estimating Junction Temperature
      2. 7.4.2 Layout Examples
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Development Support
        1. 8.1.1.1 Evaluation Modules
        2. 8.1.1.2 Spice Models
      2. 8.1.2 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. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information

Package Options

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

7.1.3 Feed-forward Capacitor (CFF)

For the adjustable-voltage version device, a feed-forward capacitor (CFF) can be connected from the OUT pin to the FB pin. CFF improves transient, noise, and PSRR performance, but is not required for regulator stability. Recommended CFF values are listed in the Recommended Operating Conditions table. A higher capacitance CFF can be used; however, the start-up time increases. For a detailed description of CFF tradeoffs, see the Pros and Cons of Using a Feedforward Capacitor with a Low-Dropout Regulator application note.

For the legacy chip, the CFF can be estimated by Equation 1:

Equation 1. TPS796

The suggested value of this capacitor for several resistor ratios is shown in the table in Figure 7-1. If this capacitor is not used (such as in a unity-gain configuration) then the minimum recommended output capacitor is 2.2 μF instead of 1 μF.