TIDUFE3 July   2025

 

  1.   1
  2.   Description
  3.   Resources
  4.   Features
  5.   Applications
  6.   6
  7. 1System Description
    1. 1.1 Key System Specifications
  8. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
    3. 2.3 Highlighted Products
      1. 2.3.1 TPS7A03
      2. 2.3.2 REF35
      3. 2.3.3 TVS3301
      4. 2.3.4 OPA391
      5. 2.3.5 AFE881H1
      6. 2.3.6 AFE882H1
      7. 2.3.7 SN74LV8T165
      8. 2.3.8 TMUX1219
  9. 3System Design Theory
  10. 4Hardware, Software, Testing Requirements, and Test Results
    1. 4.1 Hardware Requirements
    2. 4.2 Test Setup
    3. 4.3 Test Results
      1. 4.3.1 Linearity Tests
        1. 4.3.1.1 Linearity Tests Summary
      2. 4.3.2 Noise Tests and Current Histogram
        1. 4.3.2.1 Noise Tests and Current Histogram Summary
      3. 4.3.3 Step Response
        1. 4.3.3.1 Step Response Summary
      4. 4.3.4 Start-Up
      5. 4.3.5 MCU Current
        1. 4.3.5.1 MCU Current Summary
      6. 4.3.6 System Currents
        1. 4.3.6.1 Summary of System Currents
  11. 5Design and Documentation Support
    1. 5.1 Design Files
      1. 5.1.1 Schematics
      2. 5.1.2 BOM
      3. 5.1.3 PCB Layout Recommendations
        1. 5.1.3.1 Layout Prints
    2. 5.2 Tools and Software
    3. 5.3 Documentation Support
    4. 5.4 Support Resources
    5. 5.5 Trademarks
  12. 6About the Author

Noise Tests and Current Histogram

For this test, the test setup is similar to Section 4.3.1. For measuring the performance, the DAC is set to three different output currents (zero [minimum], midpoint, maximum) and the resulting current is measured 8192 times. From these values, the histogram is plotted, the other parameters are calculated from these readings.

Figure 4-17 shows the complete setup.

TIDA-010982 Test Setup Current
                    Noise Figure 4-17 Test Setup Current Noise

Figure 4-18 through Figure 4-26 show the histogram of the measured current.

TIDA-010982 Histogram AFE881 Powered
                        With 1.8V, Minimum DAC SettingFigure 4-18 Histogram AFE881 Powered With 1.8V, Minimum DAC Setting
TIDA-010982 Histogram AFE881 Powered
                        With 1.8V, Maximum DAC SettingFigure 4-20 Histogram AFE881 Powered With 1.8V, Maximum DAC Setting
TIDA-010982 Histogram AFE881 Powered
                        With 3.3V, Midpoint DAC SettingFigure 4-22 Histogram AFE881 Powered With 3.3V, Midpoint DAC Setting
TIDA-010982 Histogram AFE882 Powered
                        With 3.3V, Minimum DAC SettingFigure 4-24 Histogram AFE882 Powered With 3.3V, Minimum DAC Setting

TIDA-010982 Histogram AFE882 Powered
                        With 3.3V, Maximum DAC Setting

Figure 4-26 Histogram AFE882 Powered With 3.3V, Maximum DAC Setting
TIDA-010982 Histogram AFE881 Powered
                        With 1.8V, Midpoint DAC SettingFigure 4-19 Histogram AFE881 Powered With 1.8V, Midpoint DAC Setting
TIDA-010982 Histogram AFE881 Powered
                        With 3.3V, Minimum DAC SettingFigure 4-21 Histogram AFE881 Powered With 3.3V, Minimum DAC Setting
TIDA-010982 Histogram AFE881 Powered
                        With 3.3V, Maximum DAC SettingFigure 4-23 Histogram AFE881 Powered With 3.3V, Maximum DAC Setting
TIDA-010982 Histogram AFE882 Powered
                        With 3.3V, Midpoint DAC SettingFigure 4-25 Histogram AFE882 Powered With 3.3V, Midpoint DAC Setting