TIDU858C March   2015  – May 2021

 

  1.   Description
  2.   Resources
  3.   Features
  4.   Applications
  5.   5
  6. 1System Description
    1. 1.1 Binary Inputs or Digital Inputs
      1. 1.1.1 Binary Input Application Functionality
      2.      Common Specifications
    2. 1.2 Approaches to Binary Input Module Design
      1. 1.2.1 ADC Versus MCU Based Binary Input Module (BIM)
    3. 1.3 Measurement of Wide Inputs With Programmable Thresholds
  7. 2Design Features
    1. 2.1 Electrical Specifications
    2. 2.2 Block Diagram
      1. 2.2.1 Analog-to-Digital Converter (ADC)
        1. 2.2.1.1 ADS795x SAR ADC Family
      2. 2.2.2 Protection and Signal Conditioning
      3. 2.2.3 Digital Isolator
        1. 2.2.3.1 Host (SPI) Interfacing Using the ISO6741
      4. 2.2.4 DC Power Supply Isolator
      5. 2.2.5 Design Alternative: ADC With Digitally Programmable Threshold
        1. 2.2.5.1 ADS7128 SAR ADC With Programmable Threshold
        2. 2.2.5.2 I2C Interfacing Using the ISO1640 and Optional Altert Interface Using ISO7710
  8. 3Circuit Design and Component Selection
    1. 3.1 Analog-to-Digital Converter (ADC)
    2. 3.2 Input Signal Conditioning
      1. 3.2.1 Voltage Divider
      2. 3.2.2 TLV6002 Operational Amplifier
    3. 3.3 Isolated Interface
    4. 3.4 Isolated DC Power Supply
      1. 3.4.1 Reinforced Power Isolator: UCC12050 High-Efficiency 500-mW DC/DC Converter
    5. 3.5 Enhancements
  9. 4Testing
    1. 4.1 Test Setup and Connection Diagram
    2. 4.2 Test Data
      1. 4.2.1 Voltage Measurement Accuracy Testing
    3. 4.3 Test Results Summary
  10. 5Design Files
    1. 5.1 Schematics
    2. 5.2 Bill of Materials
    3. 5.3 Altium Project
    4. 5.4 Gerber Files
  11. 6References
  12.   Trademarks
  13. 7About the Author
  14. 8Revision History

Test Results Summary

Table 4-4 summarizes the observations for the functional and performance tests that were done on the TIDA-00420 board mounted with ADCs of varying channel counts and resolutions.

Table 4-4 AC/DC Binary Input Module Testing Summary
Tests Observations
5-V power supply with input reversal protection OK
Isolated supply output with headroom OK
Isolated supply monitoring OK
Non-isolated power supply output OK
Reference for level shifting OK
Scaling of voltage inputs and op amp output OK
Isolated ADC interface to host OK
12 or 16 channel 12-bit ADC functionality OK
12 or 16 channel 10-bit ADC functionality OK
Measurement accuracy over wide input 3 V to 320 V using a 12-bit ADC OK
Temperature and magnetic sensor output OK