Procedure

• Sweep.vi runs a special version of DC.vi, DCimbal.vi, as a subVI of Sweep.vi. Sweep.vi sends out a range of bias voltage, 5 V<V_DD <10 V (Chan0_out), in 0.5 V steps. V_SG, I_D1, and I_D2 are measured at each step. A three-column data file is saved for the Mathcad project evaluation.
  
  

  

• Note that Circuit P9.2 has the gates connected to make certain that the gate voltages are equal. There is no balancing in this circuit, as the goal is to study circuit imbalances. DCimbal.vi calls for Chan1_out = 0 V.
  
  
• Open Sweep.vi and set in the resistor values. Also open DCimbal.vi. Run DCimbal.vi to verify that the circuit is functioning properly.
  
  
• Run Sweep.vi. Set the File-Mode switch to on (Green), write in the file path (or click on the Browse button) and data file name and run the VI to obtain the data file. The data dc variables will be used in the project Mathcad file to obtain k_p and V_tpo. The values are used in a computation for a graphical comparison of measured and computed current ratios versus drain current.
  
  
• Run SweepSim.vi to obtain the data file from the graph data saved. [Note that the VSG graph is not shown in the sample Sweep.vi (above). The actual Sweep.vi has a Front Panel as the sample SweepSim.vi (below).] Copy and paste data from Sweep.vi.