SNVSCF0B October   2024  – May 2026 LM65680-Q1

ADVMIX  

  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
    2. 5.2 Pinout Design for Clearance and FMEA
  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 Descriptions
      1. 7.3.1  Input Voltage Range (VIN1, VIN2)
      2. 7.3.2  High-Voltage Bias Supply Subregulator (VCC, BIAS)
      3. 7.3.3  Precision Enable and Adjustable Input Voltage UVLO (EN/UVLO)
      4. 7.3.4  Output Voltage Setpoint (FB, BIAS)
      5. 7.3.5  Switching Frequency (RT)
      6. 7.3.6  Mode Selection and Clock Synchronization (MODE/SYNC)
        1. 7.3.6.1 Clock Synchronization
        2. 7.3.6.2 Clock Locking
      7. 7.3.7  Device Configuration (CNFG/SYNCOUT)
      8. 7.3.8  Dual-Random Spread Spectrum (DRSS)
      9. 7.3.9  High-Side MOSFET Gate Drive (BST)
      10. 7.3.10 Configurable Soft Start (SS)
        1. 7.3.10.1 Recovery From Dropout
      11. 7.3.11 Protection Features
        1. 7.3.11.1 Power-Good Monitor (PG)
        2. 7.3.11.2 Overcurrent and Short-Circuit Protection
        3. 7.3.11.3 Hiccup-Mode Protection
        4. 7.3.11.4 Thermal Shutdown
      12. 7.3.12 Two-Phase, Single-Output Operation
    4. 7.4 Device Functional Modes
      1. 7.4.1 Shutdown Mode
      2. 7.4.2 Active Mode
  9. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Power Train Components
        1. 8.1.1.1 Buck Inductor
        2. 8.1.1.2 Output Capacitors
        3. 8.1.1.3 Input Capacitors
        4. 8.1.1.4 EMI Filter
      2. 8.1.2 Error Amplifier and Compensation
      3. 8.1.3 Maximum Ambient Temperature
        1. 8.1.3.1 Derating Curves
    2. 8.2 Typical Applications
      1. 8.2.1 Design 1 – 5V, 8A Synchronous Buck Regulator With Wide Input Voltage Range and High Efficiency
        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  Choosing the Switching Frequency
          3. 8.2.1.2.3  Buck Inductor Selection
          4. 8.2.1.2.4  Input Capacitor Selection
          5. 8.2.1.2.5  Output Capacitors
          6. 8.2.1.2.6  Output Voltage Setpoint
          7. 8.2.1.2.7  Compensation Components
          8. 8.2.1.2.8  Setting the Input Voltage UVLO
          9. 8.2.1.2.9  EMI Mitigation, RDRSS
          10. 8.2.1.2.10 Bootstrap Capacitor, CBST
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Design 2 – High Efficiency, 48V to 12V, 8A, 400kHz Synchronous Buck Regulator
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
          1. 8.2.2.2.1 Buck Inductor Selection
          2. 8.2.2.2.2 Input Capacitor Selection
          3. 8.2.2.2.3 Output Capacitors
          4. 8.2.2.2.4 Output Voltage Setpoint
          5. 8.2.2.2.5 Compensation Components
          6. 8.2.2.2.6 Feedforward Capacitor
          7. 8.2.2.2.7 Soft-Start Capacitor
        3. 8.2.2.3 Application Curves
    3. 8.3 Best Design Practices
    4. 8.4 Power Supply Recommendations
    5. 8.5 Layout
      1. 8.5.1 Layout Guidelines
        1. 8.5.1.1 Thermal Design and Layout
      2. 8.5.2 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 Multiphase Design Resources
        4. 9.2.1.4 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
    1. 11.1 Tape and Reel Information

6.6 Typical Characteristics

Unless otherwise specified, TA = 25°C.

See Figure 8-7 FSW = 400kHz LO = XGL6060, 3.3μH
Figure 6-1 Efficiency, FPWM, VOUT = 5V
See Figure 8-7 FSW = 400kHz LO = XGL6060, 5.6μH
Figure 6-3 Efficiency, AUTO Mode, VOUT = 5V
LM65680-Q1 FB Voltage, Internal CompensationFigure 6-5 FB Voltage, Internal Compensation
LM65680-Q1 Fixed 5V Output Voltage Setpoint Figure 6-7 Fixed 5V Output Voltage Setpoint
LM65680-Q1 VIN Shutdown Quiescent CurrentFigure 6-9 VIN Shutdown Quiescent Current
LM65680-Q1 VIN Sleep Quiescent Current, 5V Fixed Output Figure 6-11 VIN Sleep Quiescent Current, 5V Fixed Output
VOUT = 3.3V AUTO mode LO = XGL6060, 5.6μH
Figure 6-13 No-Load Input Current, 3.3V Fixed Output, External Compensation
LM65680-Q1 High-side and Low-side MOSFET RDS(on)Figure 6-15 High-side and Low-side MOSFET RDS(on)
LM65680-Q1 Precision Enable ThresholdsFigure 6-17 Precision Enable Thresholds
LM65680-Q1 PG OV ThresholdsFigure 6-19 PG OV Thresholds
LM65680-Q1 VIN UVLO ThresholdsFigure 6-21 VIN UVLO Thresholds
LM65680-Q1 Fixed Switching Frequency – 400kHzFigure 6-23 Fixed Switching Frequency – 400kHz
VOUT = 3.3V FSW = 400kHz LO = XGL6060, 3.3μH
Figure 6-2 Efficiency, FPWM, VOUT = 3.3V
VOUT = 3.3V FSW = 400kHz LO = XGL6060, 5.6μH
Figure 6-4 Efficiency, AUTO Mode, VOUT = 3.3V
LM65680-Q1 FB Voltage, External CompensationFigure 6-6 FB Voltage, External Compensation
LM65680-Q1 Fixed 3.3V Output Voltage Setpoint Figure 6-8 Fixed 3.3V Output Voltage Setpoint
LM65680-Q1 RT Resistance vs Switching FrequencyFigure 6-10 RT Resistance vs Switching Frequency
LM65680-Q1 VIN Sleep Quiescent Current, 3.3V Fixed Output Figure 6-12 VIN Sleep Quiescent Current, 3.3V Fixed Output
VOUT = 3.3V AUTO mode LO = XGL6060, 5.6μH
Figure 6-14 No-Load Input Current, 3.3V Fixed Output, Internal Compensation
LM65680-Q1 MOSFET Current Limits – 8A OptionFigure 6-16 MOSFET Current Limits – 8A Option
LM65680-Q1 EN/UVLO Input Leakage CurrentFigure 6-18 EN/UVLO Input Leakage Current
LM65680-Q1 PG UV ThresholdsFigure 6-20 PG UV Thresholds
LM65680-Q1 VCC UVLO ThresholdsFigure 6-22 VCC UVLO Thresholds
LM65680-Q1 Fixed Switching Frequency – 2.2MHzFigure 6-24 Fixed Switching Frequency – 2.2MHz