TIDUEZ9B July   2022  – April 2023

 

  1.   Description
  2.   Resources
  3.   Features
  4.   Applications
  5.   5
  6. 1System Description
    1. 1.1 Isolated Current Measurement
    2. 1.2 Band-Pass Filter
    3. 1.3 Analog-to-Digital Conversion
    4. 1.4 Arc Detection Algorithm
    5. 1.5 Key System Specifications
  7. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
      1. 2.2.1 Current Transformer Circuit
      2. 2.2.2 Analog Band-Pass Filter
      3. 2.2.3 Analog-to-Digital Conversion
      4. 2.2.4 Power Supply
      5. 2.2.5 Debugging and Status Indication Options
    3. 2.3 Highlighted Products
      1. 2.3.1 TPS259474
      2. 2.3.2 TPS562202
      3. 2.3.3 TPS745
      4. 2.3.4 OPAx322
      5. 2.3.5 ADS8363
      6. 2.3.6 REF5025
      7. 2.3.7 TMDSCNCD280049C
  8. 3Hardware, Software, Testing Requirements, and Test Results
    1. 3.1 Hardware and Software Requirements
      1. 3.1.1 Hardware
      2. 3.1.2 Software
        1. 3.1.2.1 Arc Detection Theory
        2. 3.1.2.2 Software Implementation
    2. 3.2 Test Setup
      1. 3.2.1 ControlCARD Configuration
      2. 3.2.2 Setup for Hardware and Software Validation
      3. 3.2.3 Setup for Arc Testing
    3. 3.3 Test Results
      1. 3.3.1 Test Results of Hardware and Software Validation
      2. 3.3.2 Testing With Arcs
  9. 4Design and Documentation Support
    1. 4.1 Design Files
      1. 4.1.1 Schematics
      2. 4.1.2 BOM
    2. 4.2 Tools and Software
    3. 4.3 Support Resources
    4. 4.4 Trademarks
  10. 5About the Author
  11. 6Revision History

2.2.4 Power Supply

For the power supply an axillary supply voltage between 8 V and 16 V is necessary. Overvoltage and reverse polarity protection are implemented by using the TPS259474 eFuse. By selecting R104, R105, R112, and R113 as shown in Figure 2-6. The undervoltage lockout is set to 7.88 V, the overvoltage lockout is set to 16.15 V and the current limit is set to 0.59 A. For the exact design procedure refer to the device data sheet. A Zener diode is added to the output to protect against fast voltage transients.

There are three voltage rails necessary for this design. The first is a 5.25-V supply which is used to power the C2000 controlCARD. For this, the input voltage is stepped down using the TPS562202 buck converter. With the used values of R107 and R114 the output voltage results in 5.32 V which is slightly higher than the desired 5.25 V. The C2000 controlCARDs allow for maximum input voltage of at least 5.5 V. The 5.25-V rail is also used to generate a 5-V analog supply for the ADC and the filter stage with TPS745 as well as a 3.3-V rail for the digital supply of the ADC with TLV33P. To each supply rail a LED is added to indicate the successful power up.

GUID-20220711-SS0I-DG5C-V4PG-XHKVKFCKBJZW-low.svg Figure 2-6 Schematic Power Stage