SNVSBZ4A February   2020  – November 2021 LM61480 , LM61495 , LM62460

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 Characteristics
    7. 7.7 Switching Characteristics
    8. 7.8 System Characteristics
    9. 7.9 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  Output Voltage Selection
      2. 8.3.2  Enable EN Pin and Use as VIN UVLO
      3. 8.3.3  SYNC/MODE Uses for Synchronization
      4. 8.3.4  Clock Locking
      5. 8.3.5  Adjustable Switching Frequency
      6. 8.3.6  RESET Output Operation
      7. 8.3.7  Internal LDO, VCC UVLO, and BIAS Input
      8. 8.3.8  Bootstrap Voltage and VCBOOT-UVLO (CBOOT Pin)
      9. 8.3.9  Adjustable SW Node Slew Rate
      10. 8.3.10 Spread Spectrum
      11. 8.3.11 Soft Start and Recovery From Dropout
      12. 8.3.12 Overcurrent and Short Circuit Protection
      13. 8.3.13 Hiccup
      14. 8.3.14 Thermal Shutdown
    4. 8.4 Device Functional Modes
      1. 8.4.1 Shutdown Mode
      2. 8.4.2 Standby Mode
      3. 8.4.3 Active Mode
        1. 8.4.3.1 Peak Current Mode Operation
        2. 8.4.3.2 Auto Mode Operation
          1. 8.4.3.2.1 Diode Emulation
        3. 8.4.3.3 FPWM Mode Operation
        4. 8.4.3.4 Minimum On-time (High Input Voltage) Operation
        5. 8.4.3.5 Dropout
        6. 8.4.3.6 Recovery from Dropout
        7. 8.4.3.7 Other Fault Modes
  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  Choosing the Switching Frequency
        2. 9.2.2.2  Setting the Output Voltage
        3. 9.2.2.3  Inductor Selection
        4. 9.2.2.4  Output Capacitor Selection
        5. 9.2.2.5  Input Capacitor Selection
        6. 9.2.2.6  BOOT Capacitor
        7. 9.2.2.7  BOOT Resistor
        8. 9.2.2.8  VCC
        9. 9.2.2.9  CFF and RFF Selection
        10. 9.2.2.10 RSPSP Selection
        11. 9.2.2.11 RT Selection
        12. 9.2.2.12 RMODE Selection
        13. 9.2.2.13 External UVLO
        14. 9.2.2.14 Maximum Ambient Temperature
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
      1. 11.1.1 Ground and Thermal Considerations
    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 Glossary
    6. 12.6 Electrostatic Discharge Caution
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

9.2.1 Design Requirements

Table 9-1 provides the parameters for our detailed design procedure example:

Table 9-1 Detailed Design Parameters
DESIGN PARAMETEREXAMPLE VALUE
Input voltage13.5 V (6 V to 36 V)
Output voltage5 V
Maximum output current10 A continuous
Switching frequency400 kHz
Table 9-2 Typical External Component Values
fSW (kHz) VOUT (V) IOUT (A) L1 (µH) COUT (RATED) RFBT (kΩ) RFBB (kΩ) CIN + CHF (µF) CBOOT (µF) RBOOT (Ω) CVCC (µF) CFF (pF) RFF (kΩ)
400 5 10

2.7

 5 × 22 µF ceramic or 2 x 22 µF + 15 mΩ 150 µF 100 24.9 2 x 10 + 2 x 0.47 0.1 0 1 10 4.99
400 5 Fixed Min BOM 10 2.7 2 × 47 µF ceramic Short Open 1 x 10 + 2 x 0.47 0.1 Short 1 Open Open
400 3.3 10 2.2 3 × 47 µF ceramic or 3 x 22 µF + 15 mΩ 150 µF 100 43.2 2 x 10 + 2 x 0.47 0.1 0 1 10 4.99
400 3.3 Fixed Min BOM 10 2.2 3 × 47 µF ceramic Short Open 1 x 10 + 2 x 0.47 0.1 Short 1 Open Open
2200 5 6 0.75 3 × 22 µF ceramic or 1 x 22 µF + 15 mΩ 150 µF 100 24.9 2 x 10 + 2 x 0.47 0.1 0 1 10 4.99
2200 5 Fixed Min BOM 6 0.75 2 × 33 µF ceramic Short Open 1 x 10 + 2 x 0.47 0.1 Short 1 Open Open
2200 3.3 6 0.62 3 × 33 µF ceramic or 1 x 33 µF + 15 mΩ 150 µF 100 43.2 2 x 10 + 2 x 0.47 0.1 0 1 10 4.99
2200 3.3 Fixed Min BOM 6 0.62 2 × 47 µF ceramic Short Open 1 x 10 + 2 x 0.47 0.1 Short 1 Open Open