SNVSCF4 July   2025 LM25139-Q1

PRODUCTION DATA  

  1.   1
  2. Features
  3. Applications
  4. Description
  5. Pin Configuration and Functions
    1. 4.1 Wettable Flanks
  6. Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings 
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Typical Characteristics
  7. Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1  Input Voltage Range (VIN )
      2. 6.3.2  High-Voltage Bias Supply Regulator (VCC)
      3. 6.3.3  Precision Enable (EN)
      4. 6.3.4  Power-Good Monitor (PG)
      5. 6.3.5  Switching Frequency (RT)
      6. 6.3.6  Dual Random Spread Spectrum (DRSS)
      7. 6.3.7  Soft Start
      8. 6.3.8  Output Voltage Setpoint (FB)
      9. 6.3.9  Minimum Controllable On Time
      10. 6.3.10 Error Amplifier and PWM Comparator (FB)
      11. 6.3.11 Slope Compensation
      12. 6.3.12 Inductor Current Sense (ISNS, VOUT)
        1. 6.3.12.1 Shunt Current Sensing
        2. 6.3.12.2 Inductor DCR Current Sensing
        3. 6.3.12.3 Hiccup-Mode Current Limiting
    4. 6.4 Device Functional Modes
      1. 6.4.1 Sleep Mode
      2. 6.4.2 Forced PWM and Synchronization (FPWM/SYNC)
      3. 6.4.3 Thermal Shutdown
  8. Application and Implementation
    1. 7.1 Application Information
      1. 7.1.1 Power Train Components
        1. 7.1.1.1 Buck Inductor
        2. 7.1.1.2 Output Capacitors
        3. 7.1.1.3 Input Capacitors
        4. 7.1.1.4 Power MOSFETs
        5. 7.1.1.5 EMI Filter
      2. 7.1.2 Error Amplifier and Compensation
    2. 7.2 Typical Applications
      1. 7.2.1 Design 1 – High Efficiency 2.2MHz Synchronous Buck Regulator
        1. 7.2.1.1 Design Requirements
        2. 7.2.1.2 Detailed Design Procedure
          1. 7.2.1.2.1 Custom Design With WEBENCH® Tools
          2. 7.2.1.2.2 Buck Inductor
          3. 7.2.1.2.3 Current-Sense Components
          4. 7.2.1.2.4 Output Capacitors
          5. 7.2.1.2.5 Input Capacitors
          6. 7.2.1.2.6 Frequency Set Resistor
          7. 7.2.1.2.7 Feedback Resistors
          8. 7.2.1.2.8 Compensation Components
        3. 7.2.1.3 Application Curves
      2. 7.2.2 Design 2 – High-Efficiency, 440kHz, Synchronous Buck Regulator
        1. 7.2.2.1 Design Requirements
        2. 7.2.2.2 Detailed Design Procedure
        3. 7.2.2.3 Application Curves
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
        1. 7.4.1.1 Power Stage Layout
        2. 7.4.1.2 Gate Drive Layout
        3. 7.4.1.3 PWM Controller Layout
        4. 7.4.1.4 Thermal Design and Layout
        5. 7.4.1.5 Ground Plane Design
      2. 7.4.2 Layout Example
  9. Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Development Support
        1. 8.1.1.1 Custom Design With WEBENCH® Tools
    2. 8.2 Documentation Support
      1. 8.2.1 Related Documentation
        1. 8.2.1.1 Low-EMI Design Resources
        2. 8.2.1.2 Thermal Design Resources
        3. 8.2.1.3 PCB Layout Resources
    3. 8.3 Receiving Notification of Documentation Updates
    4. 8.4 Support Resources
    5. 8.5 Trademarks
    6. 8.6 Electrostatic Discharge Caution
    7. 8.7 Glossary
  10. Revision History
  11. 10Mechanical, Packaging, and Orderable Information

Package Options

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

Application Curves

LM25139-Q1 FPWM Efficiency
            vs IOUT
5V output
Figure 7-5 FPWM Efficiency vs IOUT
LM25139-Q1 Full-load
            Switching
8A resistive load
Figure 7-7 Full-load Switching
LM25139-Q1 Cold Crank
            Response
Cold Crank 5A load
Figure 7-9 Cold Crank Response
LM25139-Q1 Start-Up
            Characteristic
VIN step to 12V 8A resistive load
Figure 7-11 Start-Up Characteristic
LM25139-Q1 Load Transient,
            0A to 8A
VIN = 12V FPWM
Figure 7-13 Load Transient, 0A to 8A
LM25139-Q1 Bode Plot, 5V
            Output
VIN = 12V 8A resistive load
Figure 7-15 Bode Plot, 5V Output
LM25139-Q1 PFM Efficiency
            vs IOUT, Log Scale
5V output
Figure 7-6 PFM Efficiency vs IOUT, Log Scale
LM25139-Q1 PFM
            Switching
No load
Figure 7-8 PFM Switching
LM25139-Q1 Cold Crank
            Response at Lowest Vin
Cold Crank 5A load
Figure 7-10 Cold Crank Response at Lowest Vin
LM25139-Q1 ENABLE ON and
            OFF Characteristic
VIN = 12V 8A resistive load
Figure 7-12 ENABLE ON and OFF Characteristic
LM25139-Q1 Load Transient,
            4A to 8A
VIN = 12V FPWM
Figure 7-14 Load Transient, 4A to 8A
LM25139-Q1 CISPR 25 Class 5 Conducted EMI
Figure 7-16 CISPR 25 Class 5 Conducted EMI