SNVSCR9A October   2024  – December 2024 LM61480T-Q1 , LM61495T-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and Functions
  7. 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 Timing Requirements
    7. 6.7 Switching Characteristics
    8. 6.8 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Output Voltage Selection
      2. 7.3.2  Enable EN Pin and Use as VIN UVLO
      3. 7.3.3  SYNC/MODE Uses for Synchronization
      4. 7.3.4  Clock Locking
      5. 7.3.5  Adjustable Switching Frequency
      6. 7.3.6  RESET Output Operation
      7. 7.3.7  Internal LDO, VCC UVLO, and BIAS Input
      8. 7.3.8  Bootstrap Voltage and VCBOOT-UVLO (CBOOT Pin)
      9. 7.3.9  Adjustable SW Node Slew Rate
      10. 7.3.10 Spread Spectrum
      11. 7.3.11 Soft Start and Recovery From Dropout
      12. 7.3.12 Overcurrent and Short-Circuit Protection
      13. 7.3.13 Hiccup
      14. 7.3.14 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Shutdown Mode
      2. 7.4.2 Standby Mode
      3. 7.4.3 Active Mode
        1. 7.4.3.1 Peak Current Mode Operation
        2. 7.4.3.2 Auto Mode Operation
          1. 7.4.3.2.1 Diode Emulation
        3. 7.4.3.3 FPWM Mode Operation
        4. 7.4.3.4 Minimum On-time (High Input Voltage) Operation
        5. 7.4.3.5 Dropout
        6. 7.4.3.6 Recovery from Dropout
        7. 7.4.3.7 Other Fault Modes
  9. 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  Choosing the Switching Frequency
        2. 8.2.2.2  Setting the Output Voltage
        3. 8.2.2.3  Inductor Selection
        4. 8.2.2.4  Output Capacitor Selection
        5. 8.2.2.5  Input Capacitor Selection
        6. 8.2.2.6  BOOT Capacitor
        7. 8.2.2.7  BOOT Resistor
        8. 8.2.2.8  VCC
        9. 8.2.2.9  CFF and RFF Selection
        10. 8.2.2.10 RSPSP Selection
        11. 8.2.2.11 RT Selection
        12. 8.2.2.12 RMODE Selection
        13. 8.2.2.13 External UVLO
        14. 8.2.2.14 Maximum Ambient Temperature
      3. 8.2.3 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
        1. 8.4.1.1 Ground and Thermal Considerations
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Device Support
      1. 9.1.1 Third-Party Products Disclaimer
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
    3. 9.3 Receiving Notification of Documentation Updates
    4. 9.4 Support Resources
    5. 9.5 Trademarks
    6. 9.6 Glossary
    7. 9.7 Electrostatic Discharge Caution
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

パッケージ・オプション

メカニカル・データ（パッケージ｜ピン）
サーマルパッド・メカニカル・データ
発注情報

6.7 Switching Characteristics

Over operating free-air temperature range (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
OSCILLATOR (RT and SYNC PINS)
fOSC Internal oscillator frequency RT = GND 1.90 2.2 2.42 MHz
fOSC Internal oscillator frequency RT = VCC 350 400 440 kHz
fFIXED_2.2MHz Oscillator frequency measured using maximum value of RT resistor to select 2.2MHz RT = 6.81kΩ 1.95 2.2 2.42 MHz
fFIXED_0.4MHz Oscillator frequency measured using minimum value of RT resistor to select 400kHz RT = 40.2kΩ 352 400 448 kHz
fADJ Center trim oscillator frequency RT = 22.6kΩ 630 700 770 kHz
SPREAD SPECTRUM
ΔFc+ Frequency increase of internal oscillator from spread spectrum 1 4 7.5 %
ΔFc- Frequency decrease of internal oscillator from spread spectrum –8 –4 –1 %
SWITCH NODE
DMAX Maximum switch duty cycle While in frequency fold-back 98 %
fsw = 1.85MHz 87