SLVSDH5B June   2016  – March 2021 TLV627432

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison Table
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Timing Requirements
    7. 7.7 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 DCS-Control™
      2. 8.3.2 Power Save Mode Operation
      3. 8.3.3 Output Voltage Selection
      4. 8.3.4 Output Voltage Discharge of the Buck Converter
      5. 8.3.5 Undervoltage Lockout UVLO
      6. 8.3.6 Short circuit protection
    4. 8.4 Device Functional Modes
      1. 8.4.1 Enable and Shutdown
      2. 8.4.2 Device Start-up and Softstart
      3. 8.4.3 Automatic Transition Into No Ripple 100% Mode
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
        1. 9.2.2.1 Inductor Selection
        2. 9.2.2.2 Output Capacitor Selection
        3. 9.2.2.3 Input Capacitor Selection
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Device Support
      1. 12.1.1 Third-Party Products Disclaimer
    2. 12.2 Receiving Notification of Documentation Updates
    3. 12.3 Support Resources
    4. 12.4 Trademarks
    5. 12.5 Electrostatic Discharge Caution
    6. 12.6 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

9.2.2.1 Inductor Selection

The inductor value affects the peak-to-peak ripple current, the PWM-to-PFM transition point, the output voltage ripple and the efficiency. The selected inductor has to be rated for its DC resistance and saturation current. The inductor ripple current (ΔIL) decreases with higher inductance and increases with higher VIN or VOUT and can be estimated according to Equation 1.

Equation 2 calculates the maximum inductor current under static load conditions. The saturation current of the inductor should be rated higher than the maximum inductor current, as calculated with Equation 2. This is recommended because during a heavy load transient the inductor current rises above the calculated value. A more conservative way is to select the inductor saturation current according to the high-side MOSFET switch current limit, ILIMF.

Equation 1. GUID-83E5FAB3-8D11-4E0D-BC85-2316AE1E3C02-low.gif
Equation 2. GUID-5551F9D5-49E5-4EC2-996D-E1D8466AD793-low.gif

where

  • f = switching frequency
  • L = inductor value
  • ΔIL= Peak to Peak inductor ripple current
  • ILmax = Maximum Inductor current

The table below shows a list of possible inductors.

Table 9-3 List of Possible Inductors
INDUCTANCE [µH] DIMENSIONS [mm3] INDCUTOR TYPE ISAT/DCR SUPPLIER COMMENT
2.2 2.0 x 1.6 x 1.0 DFE201610C 1.4 A/170 mΩ TOKO Efficiency plot
2.2 2.0 × 1.25 × 1.0 MIPSZ2012D 2R2 0.7 A/230 mΩ FDK
2.2 2.0 x 1.2 x 1.0 744 797 752 22 0.7 A/200 mΩ Wurth Electronik
2.2 1.6 x 0.8 x 0.8 MDT1608-CH2R2M 0.7 A/300 mΩ TOKO