SNVSCU5 June   2025 LM25137-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Related Products
  6. 5 Pin Configuration and Functions
    1. 5.1 Wettable Flanks
  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 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  Input Voltage Range (VIN)
      2. 7.3.2  Bias Supply Regulator (VCC, BIAS1/VOUT1, VDDA)
      3. 7.3.3  Precision Enable (EN1, EN2)
      4. 7.3.4  Switching Frequency (RT)
      5. 7.3.5  Pulse Frequency Modulation and Synchronization (PFM/SYNC)
      6. 7.3.6  Synchronization Out (SYNCOUT)
      7. 7.3.7  Dual Random Spread Spectrum (DRSS)
      8. 7.3.8  Configurable Soft Start (RSS)
      9. 7.3.9  Output Voltage Setpoints (FB1, FB2)
      10. 7.3.10 Minimum Controllable On-Time
      11. 7.3.11 Error Amplifier and PWM Comparator (FB1, FB2, COMP1, COMP2)
        1. 7.3.11.1 Slope Compensation
      12. 7.3.12 Inductor Current Sense (ISNS1+, BIAS1/VOUT1, ISNS2+, VOUT2)
        1. 7.3.12.1 Shunt Current Sensing
        2. 7.3.12.2 Inductor DCR Current Sensing
      13. 7.3.13 MOSFET Gate Drivers (HO1, HO2, LO1, LO2)
      14. 7.3.14 Output Configurations (CNFG)
        1. 7.3.14.1 Independent Dual-Output Operation
        2. 7.3.14.2 Single-Output Interleaved Operation
        3. 7.3.14.3 Single-Output Multiphase Operation
    4. 7.4 Device Functional Modes
      1. 7.4.1 Sleep Mode
      2. 7.4.2 PFM Mode
  9. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Power Train Components
        1. 8.1.1.1 Power MOSFETs
        2. 8.1.1.2 Buck Inductor
        3. 8.1.1.3 Output Capacitors
        4. 8.1.1.4 Input Capacitors
        5. 8.1.1.5 EMI Filter
      2. 8.1.2 Error Amplifier and Compensation
    2. 8.2 Typical Applications
      1. 8.2.1 Design 1 – Dual 5V and 3.3V, 20A Buck Regulator for 12V Automotive Battery Applications
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Custom Design With WEBENCH® Tools
          2. 8.2.1.2.2 Custom Design With Excel Quickstart Tool
          3. 8.2.1.2.3 Inductor Calculations
          4. 8.2.1.2.4 Shunt Resistors
          5. 8.2.1.2.5 Ceramic Output Capacitors
          6. 8.2.1.2.6 Ceramic Input Capacitors
          7. 8.2.1.2.7 Feedback Resistors
          8. 8.2.1.2.8 Input Voltage UVLO Resistors
          9. 8.2.1.2.9 Compensation Components
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Design 2 – Two-Phase, Single-Output Synchronous Buck Regulator for Automotive ADAS Applications
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
      3. 8.2.3 Design 3 – 12V, 25A, 400kHz, Two-Phase Buck Regulator for 24V Automotive Applications
        1. 8.2.3.1 Design Requirements
        2. 8.2.3.2 Detailed Design Procedure
        3. 8.2.3.3 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
        1. 8.4.1.1 Power Stage Layout
        2. 8.4.1.2 Gate Drive Layout
        3. 8.4.1.3 PWM Controller Layout
        4. 8.4.1.4 Thermal Design and Layout
        5. 8.4.1.5 Ground Plane Design
      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. 9.1.2 Development Support
        1. 9.1.2.1 Custom Design With WEBENCH® Tools
    2. 9.2 Documentation Support
      1. 9.2.1 Related Documentation
        1. 9.2.1.1 Low-EMI Design Resources
        2. 9.2.1.2 Thermal Design Resources
        3. 9.2.1.3 PCB Layout Resources
    3. 9.3 Receiving Notification of Documentation Updates
    4. 9.4 Support Resources
    5. 9.5 Trademarks
    6. 9.6 Electrostatic Discharge Caution
    7. 9.7 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

6.6 Typical Characteristics

VIN = 12V, TJ = 25°C, unless otherwise stated.

LM25137-Q1 Efficiency vs Load, 5V Output
See Figure 8-4 VEN2 = 0V FSW = 440kHz
Figure 6-1 Efficiency vs Load, 5V Output
LM25137-Q1 Start-up Characteristic
See Figure 8-4 5A resistive loads
Figure 6-3 Start-up Characteristic
LM25137-Q1 Load Transient Response
See Figure 8-4 VOUT1 = 5V 2A/µs slew rate
Figure 6-5 Load Transient Response
LM25137-Q1 Shutdown Quiescent Current vs Temperature
VEN1 = 0V, VEN2 = 0V
Figure 6-7 Shutdown Quiescent Current vs Temperature
LM25137-Q1 Sleep Quiescent Current vs Temperature
VVOUT1 = 5V, VVOUT2 = 3.3V
Figure 6-9 Sleep Quiescent Current vs Temperature
LM25137-Q1 Fixed 3.3V Output Voltage vs TemperatureFigure 6-11 Fixed 3.3V Output Voltage vs Temperature
LM25137-Q1 Fixed 12V Output Voltage vs TemperatureFigure 6-13 Fixed 12V Output Voltage vs Temperature
LM25137-Q1 VDDA Regulation Voltage vs Temperature
IVDDA = 0mA
Figure 6-15 VDDA Regulation Voltage vs Temperature
LM25137-Q1 VCC UVLO Thresholds vs TemperatureFigure 6-17 VCC UVLO Thresholds vs Temperature
LM25137-Q1 PG UV Thresholds vs TemperatureFigure 6-19 PG UV Thresholds vs Temperature
LM25137-Q1 Current Sense Amplifier Gain vs TemperatureFigure 6-21 Current Sense Amplifier Gain vs Temperature
LM25137-Q1 EN Rising Threshold Voltage vs TemperatureFigure 6-23 EN Rising Threshold Voltage vs Temperature
LM25137-Q1 RT Resistance vs Switching FrequencyFigure 6-25 RT Resistance vs Switching Frequency
LM25137-Q1 Efficiency vs Load, 3.3V Output
See Figure 8-4 VEN1 = 0V FSW = 440kHz
Figure 6-2 Efficiency vs Load, 3.3V Output
LM25137-Q1 Shutdown Characteristic
See Figure 8-4 5A resistive loads
Figure 6-4 Shutdown Characteristic
LM25137-Q1 Switch-Node Voltages
See Figure 8-4 IOUT1 = IOUT2 = 10A
Figure 6-6 Switch-Node Voltages
LM25137-Q1 Standby Quiescent Current vs Temperature
0.6V < VEN1/2 < 1V
Figure 6-8 Standby Quiescent Current vs Temperature
LM25137-Q1 Sleep Quiescent Current vs Temperature, Ch2 Disabled
VVOUT1 = 5V, VEN2 = 0V
Figure 6-10 Sleep Quiescent Current vs Temperature, Ch2 Disabled
LM25137-Q1 Fixed 5V Output Voltage vs TemperatureFigure 6-12 Fixed 5V Output Voltage vs Temperature
LM25137-Q1 Feedback Voltage vs TemperatureFigure 6-14 Feedback Voltage vs Temperature
LM25137-Q1 VCC Regulation Voltage vs Temperature
IVCC = 20mA
Figure 6-16 VCC Regulation Voltage vs Temperature
LM25137-Q1 VCC Current Limit vs TemperatureFigure 6-18 VCC Current Limit vs Temperature
LM25137-Q1 PG OV Thresholds vs TemperatureFigure 6-20 PG OV Thresholds vs Temperature
LM25137-Q1 Current Sense Threshold vs TemperatureFigure 6-22 Current Sense Threshold vs Temperature
LM25137-Q1 Minimum On Time vs TemperatureFigure 6-24 Minimum On Time vs Temperature
LM25137-Q1 RSS Resistance vs Soft-start TimeFigure 6-26 RSS Resistance vs Soft-start Time