SNVSBR8E March   2020  – October 2025 LMQ61460

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison Table
  6. 5 Pin Configuration and Functions
  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 Timing Characteristics
    7. 6.7 Systems Characteristics
    8. 6.8 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  EN/SYNC Uses for Enable and VIN UVLO
      2. 7.3.2  EN/SYNC Pin Uses for Synchronization
      3. 7.3.3  Adjustable Switching Frequency
      4. 7.3.4  Clock Locking
      5. 7.3.5  PGOOD Output Operation
      6. 7.3.6  Internal LDO, VCC UVLO, and BIAS Input
      7. 7.3.7  Bootstrap Voltage and VCBOOT-UVLO (CBOOT Pin)
      8. 7.3.8  Adjustable SW Node Slew Rate
      9. 7.3.9  Spread Spectrum
      10. 7.3.10 Soft Start and Recovery From Dropout
      11. 7.3.11 Output Voltage Setting
      12. 7.3.12 Overcurrent and Short-Circuit Protection
      13. 7.3.13 Thermal Shutdown
      14. 7.3.14 Input Supply Current
    4. 7.4 Device Functional Modes
      1. 7.4.1 Shutdown Mode
      2. 7.4.2 Standby Mode
      3. 7.4.3 Active Mode
        1. 7.4.3.1 CCM Mode
        2. 7.4.3.2 Auto Mode – Light-Load Operation
          1. 7.4.3.2.1 Diode Emulation
          2. 7.4.3.2.2 Frequency Reduction
        3. 7.4.3.3 FPWM Mode – Light-Load Operation
        4. 7.4.3.4 Minimum On-Time (High Input Voltage) Operation
        5. 7.4.3.5 Dropout
  9. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1  Choosing the Switching Frequency
        2. 8.2.2.2  Setting the Output Voltage
        3. 8.2.2.3  Inductor Selection
        4. 8.2.2.4  Output Capacitor Selection
        5. 8.2.2.5  Input Capacitor Selection
        6. 8.2.2.6  BOOT Capacitor
        7. 8.2.2.7  BOOT Resistor
        8. 8.2.2.8  VCC
        9. 8.2.2.9  BIAS
        10. 8.2.2.10 CFF and RFF Selection
        11. 8.2.2.11 External UVLO
      3. 8.2.3 Application Curves
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
        1. 8.4.1.1 Ground and Thermal Considerations
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Documentation Support
      1. 9.1.1 Related Documentation
    2. 9.2 Receiving Notification of Documentation Updates
    3. 9.3 Support Resources
    4. 9.4 Trademarks
    5. 9.5 Electrostatic Discharge Caution
    6. 9.6 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

Package Options

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

8.2.3 Application Curves

Unless otherwise specified, the following conditions apply: VIN = 13.5 V, TA = 25°C. The circuit is shown in Figure 8-1, with the appropriate BOM from Table 8-5.

LMQ61460 LMQ61460 Efficiency
VOUT = 3.3 V fSW = 400 kHz Auto mode
Figure 8-5 LMQ61460 Efficiency
LMQ61460 LMQ61460 Efficiency
VOUT = 3.3 V fSW = 2100 kHz Auto mode
Figure 8-7 LMQ61460 Efficiency
LMQ61460 LMQ61460 Efficiency
VOUT = 5 V fSW = 400 kHz Auto mode
Figure 8-9 LMQ61460 Efficiency
LMQ61460 LMQ61460 Efficiency
VOUT = 5 V fSW = 2100 kHz Auto mode
Figure 8-11 LMQ61460 Efficiency
LMQ61460 LMQ61460 Load and Line Regulation
VOUT = 3.3 V fSW = 400 kHz Auto mode
Figure 8-13 LMQ61460 Load and Line Regulation
LMQ61460 LMQ61460 Load and Line Regulation
VOUT = 3.3 V fSW = 2100 kHz Auto mode
Figure 8-15 LMQ61460 Load and Line Regulation
LMQ61460 LMQ61460 Load and Line Regulation
VOUT = 5 V fSW = 400 kHz Auto mode
Figure 8-17 LMQ61460 Load and Line Regulation
LMQ61460 LMQ61460 Load and Line Regulation
VOUT = 5 V fSW = 2100 kHz Auto mode
Figure 8-19 LMQ61460 Load and Line Regulation
LMQ61460 LMQ61460 Dropout Curve
VOUT = 3.3 V fSW = 400 kHz Auto mode
Figure 8-21 LMQ61460 Dropout Curve
LMQ61460 LMQ61460 Dropout Curve
VOUT = 5 V fSW = 400 kHz Auto mode
Figure 8-23 LMQ61460 Dropout Curve
LMQ61460 LMQ61460 Frequency Dropout Curve
VOUT = 3.3 V fSW = 400 kHz Auto mode
Figure 8-25 LMQ61460 Frequency Dropout Curve
LMQ61460 LMQ61460 Frequency Dropout Curve
VOUT = 5 V fSW = 400 kHz Auto mode
Figure 8-27 LMQ61460 Frequency Dropout Curve
LMQ61460 LMQ61460 Switching Waveform and VOUT Ripple
VOUT = 5 V fSW = 2100 kHz Auto mode
IOUT = 50 mA VIN = 13.5 V
Figure 8-29 LMQ61460 Switching Waveform and VOUT Ripple
LMQ61460 LMQ61460 Start-Up With 50-mA Load
VOUT = 5 V fSW = 2100 kHz Auto mode
IOUT = 50 mA VIN = 13.5 V
Figure 8-31 LMQ61460 Start-Up With 50-mA Load
LMQ61460 LMQ61460 Start-Up with 3.25-A Load
VOUT = 3.3 V fSW = 2100 kHz FPWM mode
IOUT = 3.25 A VIN = 13.5 V
Figure 8-33 LMQ61460 Start-Up with 3.25-A Load
LMQ61460 LMQ61460 Short-Circuit Recovery
VOUT = 5 V fSW = 2100 kHz FPWM mode
IOUT = Short Circuit to 5 A VIN = 13.5 V
Figure 8-35 LMQ61460 Short-Circuit Recovery
LMQ61460 LMQ61460 Graceful Recovery from Dropout
VOUT = 5 V fSW = 2100 kHz FPWM mode
IOUT = 4 A VIN = 13.5 V to 4 V to 13.5 V
Figure 8-37 LMQ61460 Graceful Recovery from Dropout
LMQ61460 LMQ61460 Load Transient
VOUT = 5 V fSW = 400 kHz FPWM mode
IOUT = 0 A to 6 A to 0 A VIN = 13.5 V TR = TF = 6 µs
Figure 8-39 LMQ61460 Load Transient
LMQ61460 LMQ61460 Load Transient
VOUT = 5 V fSW = 400 kHz Auto mode
IOUT = 50 mA to 6 A to 50 mA VIN = 13.5 V TR = TF = 6 µs
Figure 8-41 LMQ61460 Load Transient
LMQ61460 LMQ61460 Load Transient
VOUT = 3.3 V fSW = 400 kHz Auto mode
IOUT = 2 A to 4 A to 2 A VIN = 13.5 V TR = TF = 2 µs
Figure 8-43 LMQ61460 Load Transient
LMQ61460 LMQ61460 Load Transient
VOUT = 5 V fSW = 2100 kHz FPWM mode
IOUT = 0 A to 6 A to 0 A VIN = 13.5 V TR = TF = 6 µs
Figure 8-45 LMQ61460 Load Transient
LMQ61460 Conducted EMI vs CISPR25 Limits (Yellow: Peak Signal, Blue: Average Signal)
VOUT = 5 V fSW = 400 kHz IOUT = 5 A
Frequency Tested: 30 MHz to 108 MHz
Figure 8-47 Conducted EMI vs CISPR25 Limits (Yellow: Peak Signal, Blue: Average Signal)
LMQ61460 Radiated EMI Bicon Vertical vs CISPR25 Limits
VOUT = 5 V fSW = 400 kHz IOUT = 5 A
Frequency Tested: 30 MHz to 300 MHz
Figure 8-49 Radiated EMI Bicon Vertical vs CISPR25 Limits
LMQ61460 Radiated EMI Log Vertical vs CISPR25 Limits
VOUT = 5 V fSW = 400 kHz IOUT = 5 A
Frequency Tested: 300 MHz to 1 GHz
Figure 8-51 Radiated EMI Log Vertical vs CISPR25 Limits
LMQ61460 Recommended Input EMI Filter
 
 
 
 
Figure 8-53 Recommended Input EMI Filter
LMQ61460 Conducted EMI vs CISPR25 Limits (Yellow: Peak Signal, Blue: Average Signal)
fSW = 2100 kHz VOUT = 5 V IOUT = 5 A
Frequency Tested: 30 MHz to 108 MHz
Figure 8-55 Conducted EMI vs CISPR25 Limits (Yellow: Peak Signal, Blue: Average Signal)
LMQ61460 Radiated EMI Bicon Vertical vs CISPR25 Limits
VOUT = 5 V fSW = 2.1 MHz IOUT = 4 A
Frequency Tested: 30 kHz to 300 MHz
Figure 8-57 Radiated EMI Bicon Vertical vs CISPR25 Limits
LMQ61460 Radiated EMI Log Vertical vs CISPR25 Limits
VOUT = 5 V fSW = 2.1 MHz IOUT = 4 A
Frequency Tested: 30 MHz to 1 GHz
Figure 8-59 Radiated EMI Log Vertical vs CISPR25 Limits
LMQ61460 Recommended Input EMI Filter
fSW = 2100 kHz
Figure 8-61 Recommended Input EMI Filter
LMQ61460 LMQ61460 Efficiency
VOUT = 3.3 V fSW = 400 kHz FPWM mode
Figure 8-6 LMQ61460 Efficiency
LMQ61460 LMQ61460 Efficiency
VOUT = 3.3 V fSW = 2100 kHz FPWM mode
Figure 8-8 LMQ61460 Efficiency
LMQ61460 LMQ61460 Efficiency
VOUT = 5 V fSW = 400 kHz FPWM mode
Figure 8-10 LMQ61460 Efficiency
LMQ61460 LMQ61460 Efficiency
VOUT = 5 V fSW = 2100 kHz FPWM mode
Figure 8-12 LMQ61460 Efficiency
LMQ61460 LMQ61460 Load and Line Regulation
VOUT = 3.3 V fSW = 400 kHz FPWM mode
Figure 8-14 LMQ61460 Load and Line Regulation
LMQ61460 LMQ61460 Load and Line Regulation
VOUT = 3.3 V fSW = 2100 kHz FPWM mode
Figure 8-16 LMQ61460 Load and Line Regulation
LMQ61460 LMQ61460 Load and Line Regulation
VOUT = 5 V fSW = 400 kHz FPWM mode
Figure 8-18 LMQ61460 Load and Line Regulation
LMQ61460 LMQ61460 Load and Line Regulation
VOUT = 5 V fSW = 2100 kHz FPWM mode
Figure 8-20 LMQ61460 Load and Line Regulation
LMQ61460 LMQ61460 Dropout Curve
VOUT = 3.3 V fSW = 2100 kHz Auto mode
Figure 8-22 LMQ61460 Dropout Curve
LMQ61460 LMQ61460 Dropout Curve
VOUT = 5 V fSW = 2100 kHz Auto mode
Figure 8-24 LMQ61460 Dropout Curve
LMQ61460 LMQ61460 Frequency Dropout Curve
VOUT = 3.3 V fSW = 2100 kHz Auto mode
Figure 8-26 LMQ61460 Frequency Dropout Curve
LMQ61460 LMQ61460 Frequency Dropout Curve
VOUT = 5 V fSW = 2100 kHz Auto mode
Figure 8-28 LMQ61460 Frequency Dropout Curve
LMQ61460 LMQ61460 Switching Waveform and VOUT Ripple
VOUT = 5 V fSW = 2100 kHz FPWM mode
IOUT = 50 mA VIN = 13.5 V
Figure 8-30 LMQ61460 Switching Waveform and VOUT Ripple
LMQ61460 LMQ61460 Start-Up With 50-mA Load
VOUT = 5 V fSW = 2100 kHz FPWM mode
IOUT = 50 mA VIN = 13.5 V
Figure 8-32 LMQ61460 Start-Up With 50-mA Load
LMQ61460 LMQ61460 Short-Circuit Protection
VOUT = 5 V fSW = 2100 kHz FPWM mode
IOUT = 5 A to Short Circuit VIN = 13.5 V
Figure 8-34 LMQ61460 Short-Circuit Protection
LMQ61460 LMQ61460 Short-Circuit Performance
VOUT = 5 V fSW = 2100 kHz FPWM mode
IOUT = Short Circuit VIN = 13.5 V
Figure 8-36 LMQ61460 Short-Circuit Performance
LMQ61460 LMQ61460 Load Transient
VOUT = 5 V fSW = 400 kHz Auto mode
IOUT = 0 A to 6 A to 0 A VIN = 13.5 V TR = TF = 6 µs
Figure 8-38 LMQ61460 Load Transient
LMQ61460 LMQ61460 Load Transient
VOUT = 5 V fSW = 400 kHz Auto mode
IOUT = 2 A to 5 A to 2 A VIN = 13.5 V TR = TF = 3 µs
Figure 8-40 LMQ61460 Load Transient
LMQ61460 LMQ61460 Load Transient
VOUT = 3.3 V fSW = 400 kHz Auto mode
IOUT = 0 A to 6 A to 0 A VIN = 13.5 V TR = TF = 6 µs
Figure 8-42 LMQ61460 Load Transient
LMQ61460 LMQ61460 Load Transient
VOUT = 5 V fSW = 2100 kHz Auto mode
IOUT = 0 A to 6 A to 0 A VIN = 13.5 V TR = TF = 6 µs
Figure 8-44 LMQ61460 Load Transient
LMQ61460 Conducted EMI vs CISPR25 Limits (Yellow: Peak Signal, Blue: Average Signal)
fSW = 400 kHz VOUT = 5 V IOUT = 5 A
Frequency Tested: 150 kHz to 30 MHz
Figure 8-46 Conducted EMI vs CISPR25 Limits (Yellow: Peak Signal, Blue: Average Signal)
LMQ61460 Radiated EMI Rod vs CISPR25 Limits
 
 
VOUT = 5 V fSW = 400 kHz IOUT = 5 A
Frequency Tested: 150 kHz to 30 MHz
Figure 8-48 Radiated EMI Rod vs CISPR25 Limits
LMQ61460 Radiated EMI Bicon Horizontal vs CISPR25 Limits
VOUT = 5 V fSW = 400 kHz IOUT = 5 A
Frequency Tested: 30 MHz to 300 MHz
Figure 8-50 Radiated EMI Bicon Horizontal vs CISPR25 Limits
LMQ61460 Radiated EMI Log Horizontal vs CISPR25 Limits
VOUT = 5 V fSW = 400 kHz IOUT = 5 A
Frequency Tested: 300 MHz to 1 GHz
Figure 8-52 Radiated EMI Log Horizontal vs CISPR25 Limits
LMQ61460 Conducted EMI vs CISPR25 Limits (Yellow: Peak Signal, Blue: Average Signal)
fSW = 2100 kHz VOUT = 5 V IOUT = 5 A
Frequency Tested: 150 kHz to 30 MHz
Figure 8-54 Conducted EMI vs CISPR25 Limits (Yellow: Peak Signal, Blue: Average Signal)
LMQ61460 Radiated EMI Red vs CISPR25 Limits
VOUT = 5 V fSW = 2.1 MHz IOUT = 4 A
Frequency Tested: 150 kHz to 30 MHz
Figure 8-56 Radiated EMI Red vs CISPR25 Limits
LMQ61460 Radiated EMI Bicon Horizontal vs CISPR25 Limits
VOUT = 5 V fSW = 2.1 MHz IOUT = 4 A
Frequency Tested: 30 MHz to 300 MHz
Figure 8-58 Radiated EMI Bicon Horizontal vs CISPR25 Limits
LMQ61460 Radiated EMI Log Horizontal vs CISPR25 Limits
VOUT = 5 V fSW = 2.1 MHz IOUT = 4 A
Frequency Tested: 300 MHz to 1 GHz
Figure 8-60 Radiated EMI Log Horizontal vs CISPR25 Limits
Table 8-5 BOM for Typical Application Curves
VOUT Frequency RFBB COUT CIN + CHF L CFF
3.3 V 400 kHz 43.2 kΩ 6 × 22 µF 2 × 4.7 µF + 2 × 100 nF 4.7 µH (XHMI6060)
3.3 V 2100 kHz 43.2 kΩ 3 × 22 µF 2 × 4.7 µF + 2 × 100 nF 1.5 µH (MAPI 4020HT) 22 pF
5 V 400 kHz 24.9 kΩ 4 × 22 µF 2 × 4.7 µF + 2 × 100 nF 4.7 µH (XHMI6060)
5 V 2100 kHz 24.9 kΩ 2 × 22 µF 2 × 4.7 µF + 2 × 100 nF 1.5 µH (MAPI 4020HT) 22 pF