SLVSE31C January   2018  – July 2018 TPSM84209

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Application
      2.      Efficiency vs Output Current
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin 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 (VIN = 5 V)
    7. 6.7 Typical Characteristics (VIN = 12 V)
    8. 6.8 Typical Characteristics (VIN = 24 V)
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Adjusting the Output Voltage
      2. 7.3.2  Input Capacitor Selection
      3. 7.3.3  Undervoltage Lockout (UVLO)
      4. 7.3.4  Output Capacitor Selection
      5. 7.3.5  Feed-Forward Capacitor
      6. 7.3.6  Operating Range
      7. 7.3.7  Output Current Rating
      8. 7.3.8  Enable (EN)
      9. 7.3.9  Internal Soft Start
      10. 7.3.10 Safe Start-Up Into Prebiased Outputs
      11. 7.3.11 Light Load Efficiency / Eco-Mode
      12. 7.3.12 Voltage Dropout
      13. 7.3.13 Overcurrent Protection
      14. 7.3.14 Output Overvoltage Protection (OVP)
      15. 7.3.15 Thermal Performance
      16. 7.3.16 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Active Mode
      2. 7.4.2 Eco-Mode Operation
      3. 7.4.3 Shutdown Mode
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Custom Design With WEBENCH® Tools
        2. 8.2.2.2 Output Voltage Setpoint
        3. 8.2.2.3 Input Capacitors
        4. 8.2.2.4 Output Capacitors
        5. 8.2.2.5 Enable Control
      3. 8.2.3 Application Waveforms
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Examples
    3. 10.3 EMI
      1. 10.3.1 EMI Plots
    4. 10.4 Package Specifications
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
    2. 11.2 Custom Design With WEBENCH® Tools
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Community Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  12. 12Mechanical, Packaging, and Orderable Information
    1. 12.1 Tape and Reel Information

7.3.2 Input Capacitor Selection

The TPSM84209 requires a ceramic input capacitor with a minimum effective capacitance of 10 μF. Use only high-quality ceramic type X5R or X7R capacitors with sufficient voltage rating. An additional 47 µF of non-ceramic capacitance is recommended for applications with transient load requirements. The voltage rating of input capacitors must be greater than the maximum input voltage. To compensate for the derating of ceramic capacitors, TI recommends a voltage rating of twice the maximum input voltage. At worst case, when operating at 50% duty cycle and maximum load, the combined ripple current rating of the input capacitors must be at least 1.25 Arms. Table 2 includes a preferred list of capacitors by vendor.

Table 2. Recommended Input Capacitors(1)

VENDOR SERIES PART NUMBER CAPACITOR CHARACTERISTICS
WORKING VOLTAGE (V) CAPACITANCE (3)
(µF)		 ESR (2)
(mΩ)
TDK X5R C3225X5R1H106K 50 10 3
Murata X7R GRM32ER71H106K 50 10 2
Murata X7R GRM32ER71J106K 63 10 2
Panasonic ZA EEHZA1H101P 50 100 28
Panasonic ZA EEHZA1J560P 63 56 30
(1) Capacitor Supplier Verification, RoHS, Lead-free and Material Details
Consult capacitor suppliers regarding availability, material composition, RoHS and lead-free status, and manufacturing process requirements for any capacitors identified in this table.
(2) Maximum ESR at 100 kHz, 25°C.
(3) Specified capacitance values