SNVSB49D April   2018  – September 2020 LMR36015

PRODUCTION DATA  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Description (continued)
  6. Device Comparison Table
  7. Pin Configuration and Functions
    1.     Pin Functions
  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 Requirements
    7. 8.7 System Characteristics
    8. 8.8 Typical Characteristics
  9. Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1 Power-Good Flag Output
      2. 9.3.2 Enable and Start-up
      3. 9.3.3 Current Limit and Short Circuit
      4. 9.3.4 Undervoltage Lockout and Thermal Shutdown
    4. 9.4 Device Functional Modes
      1. 9.4.1 Auto Mode
      2. 9.4.2 Forced PWM Operation
      3. 9.4.3 Dropout
      4. 9.4.4 Minimum Switch On-Time
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design 1: Low Power 24-V, 1.5-A PFM Converter
        1. 10.2.1.1 Design Requirements
        2. 10.2.1.2 Detailed Design Procedure
          1. 10.2.1.2.1  Custom Design With WEBENCH Tools
          2. 10.2.1.2.2  Choosing the Switching Frequency
          3. 10.2.1.2.3  Setting the Output Voltage
          4. 10.2.1.2.4  Inductor Selection
          5. 10.2.1.2.5  Output Capacitor Selection
          6. 10.2.1.2.6  Input Capacitor Selection
          7. 10.2.1.2.7  CBOOT
          8. 10.2.1.2.8  VCC
          9. 10.2.1.2.9  CFF Selection
            1. 10.2.1.2.9.1 External UVLO
          10. 10.2.1.2.10 Maximum Ambient Temperature
      2. 10.2.2 Application Curves
      3. 10.2.3 Design 2: High Density 24-V, 1.5-A FPWM Converter
        1. 10.2.3.1 Design Requirements
        2. 10.2.3.2 Detailed Design Procedure
        3. 10.2.3.3 Application Curves
    3. 10.3 What to Do and What Not to Do
  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 Device Support
      1. 13.1.1 Development Support
        1. 13.1.1.1 Custom Design With WEBENCH® Tools
    2. 13.2 Documentation Support
      1. 13.2.1 Related Documentation
    3. 13.3 Receiving Notification of Documentation Updates
    4. 13.4 Support Resources
    5. 13.5 Trademarks
    6. 13.6 Electrostatic Discharge Caution
    7. 13.7 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

Package Options

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

System Characteristics

The following specifications apply to a typical application circuit with nominal component values. Specifications in the typical (TYP) column apply to TJ = 25℃ only. Specifications in the minimum (MIN) and maximum (MAX) columns apply to the case of typical components over the temperature range of TJ = –40℃ to 150℃. These specifications are not ensured by production testing.
PARAMETERTEST CONDITIONSMINTYPMAXUNIT
VINOperating input voltage range4.260V
VOUTAdjustable output voltage regulation(1)PFM operation–1.5%2.5%
VOUTAdjustable output voltage regulation(1)FPWM operation–1.5%1.5%
ISUPPLYInput supply current when in regulationVIN = 24 V, VOUT = 3.3 V, IOUT = 0 A,
RFBT = 1 MΩ, PFM variant
26µA
DMAXMaximum switch duty cycle(2)98%
VHCFB pin voltage required to trip short-circuit hiccup mode0.4V
tHCTime between current-limit hiccup burst94ms
tDSwitch voltage dead time2ns
TSDThermal shutdown temperatureShutdown temperature170°C
TSDThermal shutdown temperatureRecovery temperature158°C
Deviation in VOUT from nominal output voltage value at VIN = 24 V, IOUT = 0 A to 1.5 A
In dropout the switching frequency drops to increase the effective duty cycle. The lowest frequency is clamped at approximately: FMIN = 1 / (tON-MAX + tOFF-MIN). DMAX = tON-MAX /(tON-MAX + tOFF-MIN).