SNVS225H February   2003  – June 2015 LP3871 , LP3874

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and 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 Diagrams
    3. 7.3 Feature Description
      1. 7.3.1 Shutdown (SD)
      2. 7.3.2 Short-Circuit Protection
      3. 7.3.3 Low Dropout Voltage
      4. 7.3.4 SENSE Pin
    4. 7.4 Device Functional Modes
      1. 7.4.1 Shutdown Mode
      2. 7.4.2 Active Mode
      3. 7.4.3 ERROR Flag Operation
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Reverse Current Path
      2. 8.1.2 Turnon Characteristics for Output Voltages Programmed To 2 V or Below
    2. 8.2 Typical Applications
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 External Capacitors
        2. 8.2.2.2 Selecting a Capacitor
        3. 8.2.2.3 Capacitor Characteristics
          1. 8.2.2.3.1 Ceramic
          2. 8.2.2.3.2 Tantalum
          3. 8.2.2.3.3 Aluminum
        4. 8.2.2.4 RFI/EMI Susceptibility
        5. 8.2.2.5 Output Noise
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
    1. 9.1 Power Dissipation
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Examples
  11. 11Device and Documentation Support
    1. 11.1 Related Links
    2. 11.2 Community Resources
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

9 Power Supply Recommendations

9.1 Power Dissipation

LP3871 and LP3874 can deliver a continuous current of 0.8 A over the full operating temperature range. A heatsink may be required depending on the maximum power dissipation and maximum ambient temperature of the application. Under all possible conditions, the junction temperature must be within the range specified under operating conditions. The total power dissipation of the device is given by:

Equation 1. LP3871 LP3874 powerdiss_SNVS225.gif

where

The maximum allowable temperature rise (TRmax) depends on the maximum ambient temperature (TAmax) of the application, and the maximum allowable junction temperature (TJmax):

Equation 2. LP3871 LP3874 maxtemp_SNVS225.gif

The maximum allowable value for junction to ambient thermal resistance, RθJA, can be calculated using the formula:

Equation 3. LP3871 LP3874 junc-to-ambient_SNVS225.gif