SNVSA47B February   2016  – July 2017 LM5165

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  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 Switching Characteristics
    7. 6.7 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1  Integrated Power MOSFETs
      2. 7.3.2  Selectable PFM or COT Mode Converter Operation
      3. 7.3.3  COT Mode Light-Load Operation
      4. 7.3.4  Low Dropout Operation and 100% Duty Cycle Mode
      5. 7.3.5  Adjustable Output Voltage (FB)
      6. 7.3.6  Adjustable Current Limit
      7. 7.3.7  Precision Enable (EN) and Hysteresis (HYS)
      8. 7.3.8  Power Good (PGOOD)
      9. 7.3.9  Configurable Soft Start (SS)
      10. 7.3.10 Thermal Shutdown
    4. 7.4 Device Functional Modes
      1. 7.4.1 Shutdown Mode
      2. 7.4.2 Standby Mode
      3. 7.4.3 Active Mode in COT
      4. 7.4.4 Active Mode in PFM
      5. 7.4.5 Sleep Mode in PFM
  8. Applications and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Applications
      1. 8.2.1 Design 1: Wide VIN, Low IQ COT Converter Rated at 5 V, 150 mA
        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 Switching Frequency - RT
          3. 8.2.1.2.3 Filter Inductor - LF
          4. 8.2.1.2.4 Output Capacitors - COUT
          5. 8.2.1.2.5 Series Ripple Resistor - RESR
          6. 8.2.1.2.6 Input Capacitor - CIN
          7. 8.2.1.2.7 Soft-Start Capacitor - CSS
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Design 2: Small Solution Size PFM Converter Rated at 3.3 V, 50 mA
        1. 8.2.2.1 Design Requirements
        2. 8.2.2.2 Detailed Design Procedure
          1. 8.2.2.2.1 Peak Current Limit Setting - RILIM
          2. 8.2.2.2.2 Switching Frequency - LF
          3. 8.2.2.2.3 Output Capacitor - COUT
          4. 8.2.2.2.4 Input Capacitor - CIN
        3. 8.2.2.3 Application Curves
      3. 8.2.3 Design 3: High Density 12-V, 75-mA PFM Converter
        1. 8.2.3.1 Design Requirements
        2. 8.2.3.2 Detailed Design Procedure
          1. 8.2.3.2.1 Peak Current Limit Setting - RILIM
          2. 8.2.3.2.2 Switching Frequency - LF
          3. 8.2.3.2.3 Input and Output Capacitors - CIN, COUT
          4. 8.2.3.2.4 Feedback Resistors - RFB1, RFB2
          5. 8.2.3.2.5 Undervoltage Lockout Setpoint - RUV1, RUV2, RHYS
          6. 8.2.3.2.6 Soft Start - CSS
        3. 8.2.3.3 Application Curves
      4. 8.2.4 Design 4: 3.3-V, 150-mA COT Converter With High Efficiency
        1. 8.2.4.1 Design Requirements
        2. 8.2.4.2 Application Curves
      5. 8.2.5 Design 5: 15-V, 150-mA, 600-kHz COT Converter
        1. 8.2.5.1 Design Requirements
        2. 8.2.5.2 Detailed Design Procedure
          1. 8.2.5.2.1 COT Output Ripple Voltage Reduction
        3. 8.2.5.3 Application Curves
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Compact PCB Layout for EMI Reduction
      2. 10.1.2 Feedback Resistor Layout
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Third-Party Products Disclaimer
      2. 11.1.2 Development Support
      3. 11.1.3 Custom Design With WEBENCH® Tools
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Related Links
    4. 11.4 Receiving Notification of Documentation Updates
    5. 11.5 Community Resources
    6. 11.6 Trademarks
    7. 11.7 Electrostatic Discharge Caution
    8. 11.8 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

Features

  • Wide Input Voltage Range of 3 V to 65 V
  • 10.5-µA No-Load Quiescent Current
  • –40°C to 150°C Junction Temperature Range
  • Fixed (3.3-V, 5-V) or Adjustable Output Voltages
  • Meets EN55022 / CISPR 22 EMI Standards
  • Integrated 2-Ω PMOS Buck Switch
    • Supports 100% Duty Cycle for Low Dropout
  • Integrated 1-Ω NMOS Synchronous Rectifier
    • Eliminates External Rectifier Diode
  • Programmable Current Limit Setpoint (4 Levels)
  • Selectable PFM or COT Mode Operation
  • 1.223-V ±1% Internal Voltage Reference
  • 900-µs Internal or Programmable Soft Start
  • Active Slew Rate Control for Low EMI
  • Diode Emulation Mode and Pulse Skipping for Ultra-High Light-Load Efficiency Performance
  • Monotonic Start-Up into Prebiased Output
  • No Loop Compensation or Bootstrap Components
  • Precision Enable and Input UVLO With Hysteresis
  • Pin-to-pin Compatible With the LM5166
  • Thermal Shutdown Protection With Hysteresis
  • 10-Pin, 3-mm × 3-mm VSON Package
  • Create a Custom Regulator Design Using WEBENCH® Power Designer

Applications

  • 4–20 mA Loop-Powered Sensors
  • Automotive and Battery-Powered Equipment
  • High-Voltage LDO Replacement
  • Industrial Control Systems
  • General-Purpose Bias Supplies

Description

The LM5165 device is a compact, easy-to-use, 3-V to 65-V, ultra-low IQ synchronous buck converter with high efficiency over wide input voltage and load current ranges. With integrated high-side and low-side power MOSFETs, up to 150-mA of output current can be delivered at fixed output voltages of 3.3 V or 5 V or at an adjustable output. The converter is designed to simplify implementation while providing options to optimize the performance for the target application. Pulse Frequency Modulation (PFM) mode is selected for optimal light-load efficiency or Constant On-Time (COT) control for nearly constant operating frequency. Both control schemes do not require loop compensation while providing excellent line and load transient response and short PWM on-time for large step-down conversion ratios.

The high-side P-channel MOSFET can operate at 100% duty cycle for lowest dropout voltage and does not require a bootstrap capacitor for gate drive. Also, the current limit setpoint is adjustable to optimize inductor selection for a particular output current requirement. Selectable and adjustable start-up timing options include minimum delay (no soft start), internally fixed (900 µs), and externally programmable soft start using a capacitor. An open-drain PGOOD indicator can be used for sequencing, fault reporting, and output voltage monitoring. The LM5165 buck converter is available in a 10-pin, 3-mm × 3-mm, thermally-enhanced VSON-10 package with 0.5-mm pin pitch.

Device Information(1)

PART # OUTPUT PACKAGE
LM5165 Adjustable VSON (10)
LM5165X 5-V fixed
LM5165Y 3.3-V fixed
  1. For all available packages, see the orderable addendum at the end of the data sheet.

Typical Schematic, Fixed Output

LM5165 Typ_app_schematic_nvsa47.gif

Typical Efficiency, VOUT = 5 V

LM5165 D101_snvsa47.gif