SLVS638D January   2006  – June 2022

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 — TL2575
    6. 6.6 Electrical Characteristics — TL2575HV
    7. 6.7 Typical Characteristics
  7. 7 Parameter Measurement Information
    1. 7.1 Test Circuits
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Feedback Connection
      2. 8.3.2 ON/OFF Input
    4. 8.4 Device Functional Modes
      1. 8.4.1 Standby Mode
  9. 9 Application and Implementation
    1. 9.1 Typical Application
      1. 9.1.1 Design Requirements
      2. 9.1.2 Detailed Design Procedure
        1. 9.1.2.1 Input Capacitor (CIN)
        2. 9.1.2.2 Output Capacitor (COUT)
        3. 9.1.2.3 Catch Diode
        4. 9.1.2.4 Inductor
        5. 9.1.2.5 Output Voltage Ripple and Transients
        6. 9.1.2.6 Grounding
        7. 9.1.2.7 Reverse Current Considerations
        8. 9.1.2.8 Buck Regulator Design Procedure
        9. 9.1.2.9 Inductor Selection Guide
      3. 9.1.3 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 Receiving Notification of Documentation Updates
    2. 12.2 Support Resources
    3. 12.3 Trademarks
    4. 12.4 Electrostatic Discharge Caution
    5. 12.5 Glossary
  13. 13Mechanical, Packaging, and Orderable Information
    1. 13.1 Package Option Addendum

Package Options

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

9.1.2.1 Input Capacitor (CIN)

For stability concerns, an input bypass capacitor (electrolytic, CIN ≥ 47 μF) needs to be located as close as possible to the regulator. For operating temperatures below –25°C, CIN may need to be larger in value. In addition, since most electrolytic capacitors have decreasing capacitances and increasing ESR as temperature drops, adding a ceramic or solid tantalum capacitor in parallel increases the stability in cold temperatures.

To extend the capacitor operating lifetime, the capacitor RMS ripple current rating should be calculated as shown in Equation 1.

Equation 1. IC,RMS >  1.2 (ton / T) ILOAD

where

  • ton/T = VOUT/VIN {buck regulator}
  • ton/T = |VOUT|/(|VOUT| + VIN) {buck-boost regulator}