SNVSAW8E March   2020  – April 2022 LM62440-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Description (continued)
  6. 6 Device Comparison Table
  7. 7 Pin Configuration and Functions
  8. 8 Specifications
    1. 8.1 Absolute Maximum Ratings
    2. 8.2 ESD Ratings
    3. 8.3 Recommended Operating Conditions
    4. 8.4 Thermal Information
    5. 8.5 Electrical Characteristics
    6. 8.6 Timing Characteristics
    7. 8.7 Systems Characteristics
    8. 8.8 Typical Characteristics
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1  EN Uses for Enable and VIN UVLO
      2. 9.3.2  MODE/SYNC Pin Operation
        1. 9.3.2.1 Level-Dependent MODE/SYNC Pin Control
        2. 9.3.2.2 Pulse-Dependent MODE/SYNC Pin Control
        3. 9.3.2.3 Clock Locking
      3. 9.3.3  PGOOD Output Operation
      4. 9.3.4  Internal LDO, VCC UVLO, and BIAS Input
      5. 9.3.5  Bootstrap Voltage and VCBOOT-UVLO (CBOOT Pin)
      6. 9.3.6  Adjustable SW Node Slew Rate
      7. 9.3.7  Spread Spectrum
      8. 9.3.8  Soft Start and Recovery From Dropout
      9. 9.3.9  Output Voltage Setting
      10. 9.3.10 Overcurrent and Short Circuit Protection
      11. 9.3.11 Thermal Shutdown
      12. 9.3.12 Input Supply Current
    4. 9.4 Device Functional Modes
      1. 9.4.1 Shutdown Mode
      2. 9.4.2 Standby Mode
      3. 9.4.3 Active Mode
        1. 9.4.3.1 CCM Mode
        2. 9.4.3.2 Auto Mode – Light-Load Operation
          1. 9.4.3.2.1 Diode Emulation
          2. 9.4.3.2.2 Frequency Reduction
        3. 9.4.3.3 FPWM Mode – Light-Load Operation
        4. 9.4.3.4 Minimum On-Time (High Input Voltage) Operation
        5. 9.4.3.5 Dropout
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
      2. 10.2.2 Detailed Design Procedure
        1. 10.2.2.1  Choosing the Switching Frequency
        2. 10.2.2.2  Setting the Output Voltage
        3. 10.2.2.3  Inductor Selection
        4. 10.2.2.4  Output Capacitor Selection
        5. 10.2.2.5  Input Capacitor Selection
        6. 10.2.2.6  BOOT Capacitor
        7. 10.2.2.7  BOOT Resistor
        8. 10.2.2.8  VCC
        9. 10.2.2.9  BIAS
        10. 10.2.2.10 CFF and RFF Selection
        11. 10.2.2.11 External UVLO
      3. 10.2.3 Application Curves
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
      1. 12.1.1 Ground and Thermal Considerations
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Documentation Support
      1. 13.1.1 Related Documentation
    2. 13.2 Receiving Notification of Documentation Updates
    3. 13.3 Support Resources
    4. 13.4 Trademarks
    5. 13.5 Electrostatic Discharge Caution
    6. 13.6 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

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

8.6 Timing Characteristics

Limits apply over the recommended operating junction temperature range of –40°C to +150°C, unless otherwise stated. Minimum and Maximum limits are specified through test, design or statistical correlation. Typical values represent the most likely parametric norm at TJ = 25°C, and are provided for reference purposes only. Unless otherwise stated the following conditions apply: VIN = 13.5 V.
Parameter Test Condition MIN TYP MAX UNIT
SWITCH NODE
tON_MIN Minimum HS switch on time VIN = 20 V, IOUT = 2 A, RBOOT short to CBOOT 55 70 ns
tON_MAX Maximum HS switch on time 9 μs
tOFF_MIN Minimum LS switch on time VIN = 4.0 V, IOUT = 1 A, RBOOT short to CBOOT 65 85 ns
tSS Time from first SW pulse to Vref at 90%, of set point. VIN ≥ 4.2 V 2 3 4 ms
tSS2 Time from first SW pulse to release of FPWM lockout if output not in regulation VIN ≥ 4.2 V 4.5 6.5 8.5 ms
tW Short circuit wait time ("Hiccup" time) 40 ms
ENABLE
tEN Turn-on delay(1) CVCC = 1 µF, time from EN high to first SW pulse if output starts at 0 V 0.7 ms
tB Blanking of EN after rising or falling edges  Low level is 0.6 V. 4 9 µs
SYNC
tPULSE_H High duration needed to be recognized as a pulse 100 ns
tPULSE_L Low duration needed to be recognized as a pulse 100 ns
tMODE Time at one level needed to indicate FPWM or auto mode 16.5 µs
tSYNC High or low signal duration in a valid synchronization signal 8 µs
CLOCK Time needed for clock to lock to a valid synchronization signal in sync cycles(1) 2048 cycle
tMEAS SYNC/MODE pin duration of resistance test upon entering Auto Mode level dependent SYNC/MODE pin operation 25 µs
POWER GOOD
tPGDFLT(rise) Delay time to PGOOD high signal 1.5 2 2.5 ms
tPGDFLT(fall) Glitch filter time constant for PGOOD function 24 µs
(1) Parameter specified using design, statistical analysis and production testing of correlated parameters; not tested in production.