SNVSB87 November   2018 LM3880-Q1

PRODUCTION DATA.  

  1. Features
  2. Applications
  3. Description
    1.     Device Images
      1.      Simple Power Supply Sequencing
  4. Revision History
  5. Pin Configuration and Functions
    1.     Pin 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
      1. 6.5.1 Timing Requirements
    6. 6.6 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Enable Pin Operation
      2. 7.3.2 Incomplete Sequence Operation
    4. 7.4 Device Functional Modes
      1. 7.4.1 Power Up With EN Pin
      2. 7.4.2 Power Down With EN Pin
  8. Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Open Drain Flags Pullup
      2. 8.1.2 Enable the Device
    2. 8.2 Typical Application
      1. 8.2.1 Simple Sequencing of Three Power Supplies
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
        3. 8.2.1.3 Application Curves
      2. 8.2.2 Sequencing Using Independent Flag Supply
    3. 8.3 Do's and Don'ts
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    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 Device Nomenclature
    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

Design Requirements

For this design example, use the parameters listed in Table 1 as the input parameters. The circuit shown in Figure 15 can have various power-down sequences depending on the sequence the part is programmed for. See Table 3 for different power-down sequence options.

Table 1. Design Parameters

DESIGN PARAMETER EXAMPLE VALUE
Input Supply voltage range 2.7 V to 5.5 V
Flag Output voltage, EN high Input Supply
Flag Output voltage, EN low 0 V
Flag Timing Delay 30 ms
Power-Up Sequence 1 - 2 - 3
Power-Down Sequence 3 - 2 - 1