TIDUEU6B September   2020  – December 2021 OPA810

 

  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 Highlighted Products
      1. 2.2.1 OPA2810
      2. 2.2.2 BUF634A
    3. 2.3 Design Considerations
      1. 2.3.1 Existing architecture
        1. 2.3.1.1 Circuit Stability Issue
        2. 2.3.1.2 Solution in Existing Architecture (Compensation Cap)
      2. 2.3.2 Proposed Design
        1. 2.3.2.1 Stability Analysis of the Proposed Design
          1. 2.3.2.1.1 Without Measurement of Voltage at Inverting Node of A2
          2. 2.3.2.1.2 With Measuring Voltage at Inverting Node of A2
        2. 2.3.2.2 RG = RF Settings and Respective Impedance Ranges
        3. 2.3.2.3 Impedance Measurement Procedure
          1. 2.3.2.3.1 Short Cal
          2. 2.3.2.3.2 Impedance Cal
          3. 2.3.2.3.3 100k Setting Calibration
          4. 2.3.2.3.4 Open Cal
          5. 2.3.2.3.5 Calculations
          6. 2.3.2.3.6 Correction in ZX
          7. 2.3.2.3.7 Data Acquisition and Processing
          8. 2.3.2.3.8 Mathematical Explanation
  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. 5Software Files
  11. 6Related Documentation
    1. 6.1 Trademarks
    2. 6.2 Third-Party Products Disclaimer
  12. 7Revision History
2.3.2.3.8 Mathematical Explanation

Let V=VO*Sin(ωt+α) be any signal, if it is multiplied by a unity magnitude square wave with 0° phase then the resultant output is as shown in Figure 2-10.

GUID-669D0C6F-0E16-42CD-A1E3-1C773B2A2140-low.gif Figure 2-10 Square Wave Modulation

Let the average value of the output be V1,

Equation 14. GUID-86350E37-CCE7-4FB5-81B9-79E5D8946C41-low.gif

Similarly when V is multiplied by square wave with 90° phase, the resultant output is as shown in Figure 2-11.

GUID-7CDB6AE0-6991-499C-A009-4B9AFFDACCF4-low.gifFigure 2-11 Square Wave Modulation with 90° phase

Let the average value of the output be V2,

Equation 15. GUID-1DC38528-0C74-48D7-B5EE-1DD5034A2443-low.gif

Where k is equal to 4/π.

Using Equation 16 and Equation 17, we get

Equation 16. GUID-CE357DC1-1CE5-4719-AC50-52F4402C50AE-low.gif
Equation 17. GUID-7D1E4F2E-2B9B-495F-BA06-1B4316604062-low.gif

In this way, both the magnitude ‘|V|’ and phase ‘α’ of any signal V is estimated.