SNVSB35C May   2018  – November 2024

PRODUCTION DATA  

  1.   1
  2. Features
  3. Applications
  4. Description
  5. Pin Configuration and Functions
  6. Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics Per Buck
    6. 5.6 Typical Characteristics
  7. Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Soft Start
      2. 6.3.2 Power Good
      3. 6.3.3 Precision Enable
    4. 6.4 Device Functional Modes
      1. 6.4.1 Output Overvoltage Protection
      2. 6.4.2 Undervoltage Lockout
      3. 6.4.3 Current Limit
      4. 6.4.4 Thermal Shutdown
  8. Application and Implementation
    1. 7.1 Application Information
      1. 7.1.1 Programming Output Voltage
      2. 7.1.2 VINC Filtering Components
      3. 7.1.3 Using Precision Enable and Power Good
      4. 7.1.4 Overcurrent Protection for HTSSOP-20 Package
      5. 7.1.5 Current Limit and Short-Circuit Protection for WQFN-16 Package
    2. 7.2 Typical Applications
      1. 7.2.1 2.2-MHz, 0.8-V Typical High-Efficiency Application Circuit
        1. 7.2.1.1 Design Requirements
        2. 7.2.1.2 Detailed Design Procedure
          1. 7.2.1.2.1 Custom Design With WEBENCH® Tools
          2. 7.2.1.2.2 Inductor Selection
          3. 7.2.1.2.3 Input Capacitor Selection
          4. 7.2.1.2.4 Output Capacitor
          5. 7.2.1.2.5 Calculating Efficiency and Junction Temperature
        3. 7.2.1.3 Application Curves
      2. 7.2.2 2.2-MHz, 1.8-V Typical High-Efficiency Application Circuit
        1. 7.2.2.1 Design Requirements
        2. 7.2.2.2 Detailed Design Procedure
        3. 7.2.2.3 Application Curves
      3. 7.2.3 LM26420-Q12.2-MHz, 2.5-V Typical High-Efficiency Application Circuit
        1. 7.2.3.1 Design Requirements
        2. 7.2.3.2 Detailed Design Procedure
        3. 7.2.3.3 Application Curves
    3. 7.3 Power Supply Recommendations
      1. 7.3.1 Power Supply Recommendations - HTSSOP-20 Package
      2. 7.3.2 Power Supply Recommendations - WQFN-16 Package
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
      3. 7.4.3 Thermal Considerations
        1. 7.4.3.1 Method 1: Silicon Junction Temperature Determination
        2. 7.4.3.2 Thermal Shutdown Temperature Determination
  9. Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Third-Party Products Disclaimer
      2. 8.1.2 Custom Design With WEBENCH® Tools
    2. 8.2 Documentation Support
      1. 8.2.1 Related Documentation
    3. 8.3 Receiving Notification of Documentation Updates
    4. 8.4 Support Resources
    5. 8.5 Trademarks
    6. 8.6 Electrostatic Discharge Caution
    7. 8.7 Glossary
  10. Revision History
  11. 10Mechanical, Packaging, and Orderable Information

Electrical Characteristics Per Buck

Over operating free-air temperature range (unless otherwise noted)
PARAMETERTEST CONDITIONSMINTYPMAXUNIT
VFBFeedback voltage0.7880.80.812V
ΔVFB/VINFeedback Voltage line regulationVIN = 3 V to 5.5 V0.05%/V
IBFeedback input bias current0.4100nA
UVLOUndervoltage lockoutVIN rising, HTSSOP-20 package2.6282.9V
VIN Rising, WQFN-16 Package 2.75 2.9 V
VIN falling, HTSSOP-20 package22.3V
VIN Falling, WQFN-16 Package 2 2.5 V
UVLO hysteresisHTSSOP-20 Package330mV
WQFN-16 Package 260 mV
FSWSwitching frequency2.012.22.65MHz
FFBFrequency foldbackHTSSOP-20 Package300kHz
DMAXMaximum duty cycle86%91.5%
RDSON_TOPTOP switch on resistanceWQFN-16 package75135mΩ
HTSSOP-20 package70135
RDSON_BOTBOTTOM switch on resistanceWQFN-16 package55100mΩ
HTSSOP-20 package4580
ICL_TOPTOP switch current limitVIN = 3.3 V2.43.3A
ICL_BOTBOTTOM Switch reverse current limitVIN = 3.3 V, HTSSOP-20 Package0.40.75A
VIN = 3.3V, WQFN-16 Package 0.4 1.0 A
ΔΦPhase shift between SW1 and SW2160180200°
VEN_THEnable threshold voltage0.971.041.12V
Enable threshold hysteresis0.15
ISW_TOPSwitch leakage–0.7µA
IENEnable pin currentSink/source5nA
VPG-TH-UUpper Power-Good thresholdFB pin voltage rising8489251,008mV
Upper Power-Good hysteresis40mV
VPG-TH-LLower Power-Good thresholdFB pin voltage rising656710791mV
Lower Power-Good hysteresis40mV
IQVINCVINC quiescent current (non-switching) with both outputs on VFB = 0.95 V3.35mA
VINC quiescent current (switching) with both outputs on VFB = 0.7 V4.76.2
VINC quiescent current (shutdown) VEN = 0 V0.05µA
IQVINDVIND quiescent current (non-switching) VFB = 0.95 V0.91.5mA
VIND quiescent current (switching) VFB = 0.7 V1115
IQVINDVIND Quiescent Current (switching)LM26420Q0 VFB = 0.7 V1118mA
IQVINDVIND quiescent current (shutdown) VEN = 0 V0.1µA
TSDThermal shutdown temperature165°C