SNVS853E August   2012  – August 2018 LMZ21701

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Schematic
      2.      Efficiency for VIN = 12 V
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin Functions
  6. 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
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Package Construction
    4. 7.4 Feature Description
      1. 7.4.1 Input Undervoltage Lockout
      2. 7.4.2 Enable Input (EN)
      3. 7.4.3 Soft Start and Tracking Function (SS)
      4. 7.4.4 Power Good Function (PG)
      5. 7.4.5 Output Voltage Setting
      6. 7.4.6 Output Current Limit and Output Short Circuit Protection
      7. 7.4.7 Thermal Protection
    5. 7.5 Device Functional Modes
      1. 7.5.1 PWM Mode Operation
      2. 7.5.2 PSM Operation
  8. 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 Custom Design With WEBENCH® Tools
        2. 8.2.2.2 Input Capacitor (CIN)
        3. 8.2.2.3 Output Capacitor (COUT)
        4. 8.2.2.4 Soft-start Capacitor (CSS)
        5. 8.2.2.5 Power Good Resistor (RPG)
        6. 8.2.2.6 Feedback Resistors (RFBB and RFBT)
      3. 8.2.3 Application Curves
        1. 8.2.3.1 VOUT = 1.2 V
        2. 8.2.3.2 VOUT = 1.8 V
        3. 8.2.3.3 VOUT = 2.5 V
        4. 8.2.3.4 VOUT = 3.3 V
        5. 8.2.3.5 VOUT = 5.0 V
    3. 8.3 Do's and Don'ts
  9. 9 Power Supply Recommendations
    1. 9.1 Voltage Range
    2. 9.2 Current Capability
    3. 9.3 Input Connection
      1. 9.3.1 Voltage Drops
      2. 9.3.2 Stability
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Minimize the High di/dt Loop Area
      2. 10.1.2 Protect the Sensitive Nodes in the Circuit
      3. 10.1.3 Provide Thermal Path and Shielding
    2. 10.2 Layout Example
      1. 10.2.1 High Density Layout Example for Space Constrained Applications
        1. 10.2.1.1 35 mm² Solution Size (Single Sided)
  11. 11Device and Documentation Support
    1. 11.1 Device Support
      1. 11.1.1 Development Support
        1. 11.1.1.1 Custom Design With WEBENCH® Tools
    2. 11.2 Trademarks
    3. 11.3 Electrostatic Discharge Caution
    4. 11.4 Glossary
  12. 12Mechanical, Packaging, and Orderable Information
    1. 12.1 Tape and Reel Information

8.2.3.2 VOUT = 1.8 V

LMZ21701 TYP_SCH.gifFigure 32. Typical Applications Circuit
LMZ21701 D015_LMZ21701_25C_1.8VOUT_EFFICIENCY_LOG_SNVS853.gifFigure 34. Efficiency VOUT = 1.8 V
LMZ21701 LMZ21701_1.8VOUT_LOAD_TRANS_100mA_to_1000mA_snvs853.gifFigure 36. Load Transient VOUT = 1.8 V
LMZ21701 LMZ21701_1.8VOUT_RIPPLE_20MHzBW_snvs853.gifFigure 38. 20 MHz Oscilloscope Bandwidth
Output Voltage Ripple VOUT = 1.8 V
LMZ21701 LMZ21701_FSW_1.8VOUT_snvs853.pngFigure 40. Typical Switching Frequency at 1000 mA Load VOUT = 1.8 V
LMZ21701 D016_LMZ21701_25C_1.8VOUT_LINE_AND_LOAD_REG_LOG_SNVS853.gifFigure 42. Line and Load Regulation VOUT = 1.8 V
LMZ21701 1.8V_BOM_snvs853.gifFigure 33. External Component Values
(VOUT = 1.8 V)
LMZ21701 LMZ21701_25C_1.8VOUT_POWER_DISSIPATION_snvs853.pngFigure 35. Power Dissipation VOUT = 1.8 V
LMZ21701 LMZ21701_1.8VOUT_STARTUP_snvs853.gifFigure 37. Startup VOUT = 1.8 V
LMZ21701 LMZ21701_1.8VOUT_RIPPLE_500MHzBW_snvs853.gifFigure 39. 500 MHz Oscilloscope Bandwidth, 3x1000 pF additional output capacitance
Output Voltage Ripple and HF Noise VOUT = 1.8 V
LMZ21701 LMZ21701_ICL_1.8V_85C_snvs853.pngFigure 41. Typical Current Limit VOUT = 1.8 V, TA = 85 °C
LMZ21701 LMZ21701SIL_1.8VO_47CperW_snvs853.pngFigure 43. Thermal Derating for θJA= 47ºC/W VOUT = 1.8 V