SLVSG94C November   2023  – June 2024 TPS62914 , TPS62916 , TPS62918

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  Smart Config (S-CONF)
      2. 6.3.2  Device Enable (EN/SYNC)
      3. 6.3.3  Device Synchronization (EN/SYNC)
      4. 6.3.4  Spread Spectrum Modulation
      5. 6.3.5  Output Discharge
      6. 6.3.6  Undervoltage Lockout (UVLO)
      7. 6.3.7  Power-Good Output
      8. 6.3.8  Noise Reduction and Soft-Start Capacitor (NR/SS)
      9. 6.3.9  Current Limit and Short-Circuit Protection
      10. 6.3.10 Thermal Shutdown
    4. 6.4 Device Functional Modes
      1. 6.4.1 Fixed Frequency Pulse Width Modulation
      2. 6.4.2 Low Duty Cycle Operation
      3. 6.4.3 High Duty Cycle Operation (100% Duty Cycle)
      4. 6.4.4 Second Stage L-C Filter Compensation (Optional)
  8. Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Applications
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
        1. 7.2.2.1 Custom Design With WEBENCH® Tools
        2. 7.2.2.2 External Component Selection
          1. 7.2.2.2.1 Switching Frequency Selection
          2. 7.2.2.2.2 Inductor Selection for the First L-C Filter
          3. 7.2.2.2.3 Output Capacitor Selection
          4. 7.2.2.2.4 Ferrite Bead Selection for Second L-C Filter
          5. 7.2.2.2.5 Input Capacitor Selection
          6. 7.2.2.2.6 Setting the Output Voltage
          7. 7.2.2.2.7 Bootstrap Capacitor Selection
          8. 7.2.2.2.8 NR/SS Capacitor Selection
      3. 7.2.3 Application Curves
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
  9. Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Third-Party Products Disclaimer
      2. 8.1.2 Development Support
        1. 8.1.2.1 Custom Design With WEBENCH® Tools
    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
Output Capacitor Selection

The effective output capacitance can range from 80 μF (minimum) up to 400 μF (maximum) for a single L-C system design. When using a second L-C filter, the first L-C filter must have output capacitance between 80 μF and 160 μF, the second stage L-C filter (if used) must have at least 20 μF of capacitance, and the total capacitance for both L-C filters must be less than 400 μF. Load transient testing and measuring the bode plot are good ways to verify stability.

Note: For designs requiring cold temperature (< –10°C) operation, TI recommends to use a minimum effective output capacitance of 120 μF for a single L-C system design or within the first L-C filter when using a second L-C filter design.

TI recommends ceramic capacitors (X5R or X7R). Ceramic capacitors have a DC-Bias effect, which has a strong influence on the final effective capacitance. Choose the right capacitor carefully in combination with considering the package size and voltage rating. The ESR and ESL of the output capacitor are also important considerations in selecting the output capacitors for low noise applications. Smaller package sizes typically have lower ESL and ESR. TI recommends 0805 or smaller packages, as long as the packages provide the required capacitance and voltage rating for stable operation. Table 7-6 lists recommended output capacitors.

Table 7-5 Recommended Output Capacitors
CAPACITOR TYPECAPACITOR VALUEMANUFACTURERVOLTAGE (V)PACKAGE
Bulk Capacitor22 μF, X7STDK C2012X7S1A226M125AC100805
Bulk Capacitor47 μF, X7RMurata GRM32ER71A476ME15L101210