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

6.6 Typical Characteristics

Unless otherwise specified the following conditions apply: VIN = 12 V, TA = 25°C
LMZ21701 D012_LMZ21701_PACKAGE_THERMAL_VS_PCB_SNVS853.gifFigure 2. Package Thermal Resistance vs. Board Copper Area
LMZ21701 D006_LMZ21701_PD_85C_1.8VOUT_SNVS853.gif
VOUT = 1.8 V TA = 85ºC
Figure 4. Power Dissipation
LMZ21701 D008_LMZ21701_PD_85C_3.3VOUT_SNVS853.gif
VOUT = 3.3 V TA = 85ºC
Figure 6. Power Dissipation
LMZ21701 D011_LMZ21701_85C_DROPOUT_5VOUT_SNVS853.gif
VOUT = 5.0 V TA = 85ºC
Figure 8. Dropout
LMZ21701 D004_LMZ21701_Radiated_EMI_SNVS853.gif
VIN= 12 V VOUT = 3.3 V IOUT = 1 A
Figure 10. Radiated EMI on EVM
LMZ21701 D005_LMZ21701_PD_85C_1.2VOUT_SNVS853.gif
VOUT = 1.2 V TA = 85ºC
Figure 3. Power Dissipation
LMZ21701 D007_LMZ21701_PD_85C_2.5VOUT_SNVS853.gif
VOUT = 2.5 V TA = 85ºC
Figure 5. Power Dissipation
LMZ21701 D009_LMZ21701_PD_85C_5.0VOUT_SNVS853.gif
VOUT = 5.0 V TA = 85ºC
Figure 7. Power Dissipation
LMZ21701 D010_LMZ21701_85C_DROPOUT_3.3VOUT_SNVS853.gif
VOUT = 3.3 V TA = 85ºC
Figure 9. Dropout
LMZ21701 D003_LMZ21701_ConductedEMI_2.2uH_1uF_Filter_SNVS853.gif
VIN= 12 V VOUT = 3.3 V IOUT = 1 A
Lf = 2.2 µH Cf = 1.0 µF
Figure 11. Conducted EMI on EVM