TIDUET0A November   2019  – July 2020

 

  1.   Description
  2.   Resources
  3.   Features
  4.   Applications
  5.   5
  6. 1System Description
    1. 1.1 Key System Specifications
  7. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
    3. 2.3 Highlighted Products
      1. 2.3.1 TPS61088-Q1
      2. 2.3.2 LMR33630-Q1
      3. 2.3.3 TPS7A2501
      4. 2.3.4 ATL431AIBDZR
    4. 2.4 System Design Theory
  8. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Required Hardware and Software
      1. 3.1.1 Hardware
    2. 3.2 Testing and Results
      1. 3.2.1 Test Setup
      2. 3.2.2 Test Results
  9. 4Design Files
    1. 4.1 Schematics
    2. 4.2 Bill of Materials
    3. 4.3 PCB Layout Recommendations
      1. 4.3.1 Layout Prints
    4. 4.4 Altium Project
    5. 4.5 Gerber Files
    6. 4.6 Assembly Drawings
  10. 5Related Documentation
    1. 5.1 Trademarks
    2. 5.2 Third-Party Products Disclaimer
  11. 6About the Author
  12. 7Revision History

1 System Description

In the ECall application, when the main battery voltage is high, all of the related circuits in the ECall is supplied by the main battery through a buck converter. When the main battery voltage drops to a low level, the buck converter browns out, the back-up battery starts working, it supplies the equipment through a boost converter. Figure 1-1 shows a traditional ECall block diagram. Besides a high-voltage buck converter, it uses two boost converters and one charger and because of the two boost converters, this is redundant and reduces efficiency.

GUID-C2C8EDFF-6A98-4FA0-B593-BD07ACE38CD7-low.pngFigure 1-1 Traditional ECall Block Diagram

The TIDA-050031 takes into consideration cost and the size while avoiding the redundancy of a traditional ECall block diagram in Figure 1. This reference design delivers a simple and low cost backup power circuit for the automotive ECall application. The structure is very simple. Only one boost converter is used in the circuit. The boost converter TPS61088-Q1 can output 8 V/1.6A with high efficiency at 2 V input voltage. So the minimum backup battery voltage can be down to 2 V. Besides extending the lifetime of the backup battery, the TIDA-050031 is also flexible and less redundancy.