SNVSC03B June   2021  – February 2025 LM25148-Q1

PRODUCTION DATA  

  1.   1
  2. Features
  3. Applications
  4. Description
  5. Description (continued)
  6. Orderable Part Numbers
  7. Pin Configuration and Functions
    1. 6.1 Wettable Flanks
  8. 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 Typical Characteristics
  9. Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1  Input Voltage Range (VIN)
      2. 8.3.2  High-Voltage Bias Supply Regulator (VCC, VCCX, VDDA)
      3. 8.3.3  Precision Enable (EN)
      4. 8.3.4  Power-Good Monitor (PG)
      5. 8.3.5  Switching Frequency (RT)
      6. 8.3.6  Dual Random Spread Spectrum (DRSS)
      7. 8.3.7  Soft Start
      8. 8.3.8  Output Voltage Setpoint (FB)
      9. 8.3.9  Minimum Controllable On Time
      10. 8.3.10 Error Amplifier and PWM Comparator (FB, EXTCOMP)
      11. 8.3.11 Slope Compensation
      12. 8.3.12 Inductor Current Sense (ISNS+, VOUT)
        1. 8.3.12.1 Shunt Current Sensing
        2. 8.3.12.2 Inductor DCR Current Sensing
      13. 8.3.13 Hiccup Mode Current Limiting
      14. 8.3.14 High-Side and Low-Side Gate Drivers (HO, LO)
      15. 8.3.15 Output Configurations (CNFG)
      16. 8.3.16 Single-Output Dual-Phase Operation
    4. 8.4 Device Functional Modes
      1. 8.4.1 Sleep Mode
      2. 8.4.2 Pulse Frequency Modulation and Synchronization (PFM/SYNC)
      3. 8.4.3 Thermal Shutdown
  10. Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 Power Train Components
        1. 9.1.1.1 Buck Inductor
        2. 9.1.1.2 Output Capacitors
        3. 9.1.1.3 Input Capacitors
        4. 9.1.1.4 Power MOSFETs
        5. 9.1.1.5 EMI Filter
      2. 9.1.2 Error Amplifier and Compensation
    2. 9.2 Typical Applications
      1. 9.2.1 Design 1 – High Efficiency 2.1MHz Synchronous Buck Regulator
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Custom Design with WEBENCH® Tools
          2. 9.2.1.2.2 Buck Inductor
          3. 9.2.1.2.3 Current-Sense Resistance
          4. 9.2.1.2.4 Output Capacitors
          5. 9.2.1.2.5 Input Capacitors
          6. 9.2.1.2.6 Frequency Set Resistor
          7. 9.2.1.2.7 Feedback Resistors
          8. 9.2.1.2.8 Compensation Components
        3. 9.2.1.3 Application Curves
      2. 9.2.2 Design 2 – High Efficiency 440-kHz Synchronous Buck Regulator
        1. 9.2.2.1 Design Requirements
        2. 9.2.2.2 Detailed Design Procedure
        3. 9.2.2.3 Application Curves
      3. 9.2.3 Design 3 – Dual-Phase 400-kHz 20-A Synchronous Buck Regulator
        1. 9.2.3.1 Design Requirements
        2. 9.2.3.2 Detailed Design Procedure
        3. 9.2.3.3 Application Curves
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
        1. 9.4.1.1 Power Stage Layout
        2. 9.4.1.2 Gate-Drive Layout
        3. 9.4.1.3 PWM Controller Layout
        4. 9.4.1.4 Thermal Design and Layout
        5. 9.4.1.5 Ground Plane Design
      2. 9.4.2 Layout Example
  11. 10Device and Documentation Support
    1. 10.1 Device Support
      1. 10.1.1 Development Support
        1. 10.1.1.1 Custom Design with WEBENCH® Tools
    2. 10.2 Documentation Support
      1. 10.2.1 Related Documentation
        1. 10.2.1.1 PCB Layout Resources
        2. 10.2.1.2 Thermal Design Resources
    3. 10.3 Receiving Notification of Documentation Updates
    4. 10.4 Support Resources
    5. 10.5 Trademarks
    6. 10.6 Electrostatic Discharge Caution
    7. 10.7 Glossary
  12. 11Revision History
  13. 12Mechanical, Packaging, and Orderable Information

Typical Characteristics

VIN = 12 V, unless otherwise specified

LM25148-Q1 Efficiency vs
            Load
VOUT = 5 V FSW = 440 kHz
Figure 7-1 Efficiency vs Load
LM25148-Q1 Shutdown
            Current vs Temperature
VEN = 0 V
Figure 7-3 Shutdown Current vs Temperature
LM25148-Q1 Sleep2 Current
            vs Temperature
VVOUT = 5 V 1.03 V ≤ VEN ≤ 42 V
Figure 7-5 Sleep2 Current vs Temperature
LM25148-Q1 Fixed 5-V
            Output Voltage vs TemperatureFigure 7-7 Fixed 5-V Output Voltage vs Temperature
LM25148-Q1 PG OV
            Thresholds vs TemperatureFigure 7-9 PG OV Thresholds vs Temperature
LM25148-Q1 VCC Regulation
            Voltage vs TemperatureFigure 7-11 VCC Regulation Voltage vs Temperature
LM25148-Q1 VCC Current
            Limit vs TemperatureFigure 7-13 VCC Current Limit vs Temperature
LM25148-Q1 VDDA UVLO
            Thresholds vs TemperatureFigure 7-15 VDDA UVLO Thresholds vs Temperature
LM25148-Q1 Current Sense
            (CS) Threshold vs TemperatureFigure 7-17 Current Sense (CS) Threshold vs Temperature
LM25148-Q1 Minimum On Time
            (HO) vs TemperatureFigure 7-19 Minimum On Time (HO) vs Temperature
LM25148-Q1 Switching
            Frequency vs Temperature
RRT = 9.09 kΩ
Figure 7-21 Switching Frequency vs Temperature
LM25148-Q1 Efficiency vs
            Load, Log Scale
VOUT = 5 V FSW = 440 kHz
Figure 7-2 Efficiency vs Load, Log Scale
LM25148-Q1 Sleep1 Current
            vs Temperature
VVOUT = 3.3 V 1.03 V ≤ VEN ≤ 42 V
Figure 7-4 Sleep1 Current vs Temperature
LM25148-Q1 Fixed 3.3-V
            Output Voltage vs TemperatureFigure 7-6 Fixed 3.3-V Output Voltage vs Temperature
LM25148-Q1 Feedback
            Voltage vs TemperatureFigure 7-8 Feedback Voltage vs Temperature
LM25148-Q1 PG UV
            Thresholds vs TemperatureFigure 7-10 PG UV Thresholds vs Temperature
LM25148-Q1 VCC UVLO
            Thresholds vs TemperatureFigure 7-12 VCC UVLO Thresholds vs Temperature
LM25148-Q1 VDDA Regulation
            Voltage vs TemperatureFigure 7-14 VDDA Regulation Voltage vs Temperature
LM25148-Q1 VCCX On, Off
            Thresholds vs TemperatureFigure 7-16 VCCX On, Off Thresholds vs Temperature
LM25148-Q1 Current Sense
            (CS) Amplifier Gain vs TemperatureFigure 7-18 Current Sense (CS) Amplifier Gain vs Temperature
LM25148-Q1 Soft-Start Time
            vs TemperatureFigure 7-20 Soft-Start Time vs Temperature