Characterization of the PMOS Transistor for Circuit Simulation

VTO

V_tno, V_tpo

Zero VSB threshold voltage.

KP

Transconductance parameter.

GAMMA

g_n g_p

Threshold voltage parameter.

LAMBDA

l_n l_p

Active-region slope parameter.

CD4007 Pin Diagram

Output characteristic low-voltage conductance.

Output characteristic for full linear range (0<V_SD<V_effp).

Active region transfer characteristic and output characteristic (V_SD>V_effp).

Active region relation solved for V_SG.

Components

LabVIEW Computations

Procedure

Run PMOSlinear.vi and adjust VSGstart(V) such that Veffpstart(V) > 0.5 V. The maximum I_D is set for 0.1 V. Run the VI to obtain parameters as indicated in the Front Panel. Default and save the Front Panel to save information for the Mathcad analysis.

Components

LabVIEW Computations

Procedure

Run PMOSparsub.vi with VSD = 3 V and VSD = 9 V. VDD (Chan0_out) starts at 2 V such that the minimum current is IDmin = (2 V - VSGmin)/RS. ID stops automatically at ID = 500 mA or Chan0_out = 10 V. Verify that the VI functions properly. PMOSparsub.vi will run as a subVI of the next VI.

Components

LabVIEW Computations

Procedure

Run PMOSparam.vi to run subVI PMOSparsub.vi at VSD = 3 V and VSD = 9 V to resolve Lambda and final values of kp and Vtpo. Default and save the Front Panel to save the parameter values for the Mathcad results analysis file.

Components

LabVIEW Computations

Linear Region

Active Region

Procedure

Install PMOS parameters from P3.6 into the Front Panel of PMOSoutput.vi. A given VSD sweep will halt at Chan0_out = 10 V. Set VSGstart(V) as necessary to obtain I_D mA for VSD in the active region. Verify that the measured data and SPICE calculation agree reasonably well. Write in you file path and save a data file for Mathcad. The file will contain the data points for the highest current output characteristic. Default Front Panel and save. These data will be used in the Mathcad analysis file.

With the data defaulted and saved in the graph of the VI, a data file can be obtained at a later time. From the Diagram of PMOSoutput.vi, click on XYtoDataFile.vi, copy the data from PMOSoutput.vi, and paste it into the Control Graph of XYtoDataFile.vi. Name the path and data file and run the VI. XYtoDataFile.vi is located in the User.lib in the LabVIEW folder. Therefore, it can also be opened from the Diagram of a VI under Functions>>User Libraries>>Dat_File.

LabVIEW Computations

Straight-line curve fit from active region data:

I_D = Slope · V_SD + I_Do

l_p = Slope/I_Do k_p = I_Do/V_effp²

Procedure

Lambda.vi is configured for Enable Data Base Access to read the data from PMOSoutput.vi. Lambda.vi can read all of the Front Panel information in PMOSoutput.vi when a log of the Front Panel has been obtained.

From the Diagram of Lambda.vi, open PMOSoutput.vi. Obtain a data log of the Front Panel of the PMOSoutput.vi (under Operate Menu).

Run Lambda.vi to read the graph of measured data (from PMOSoutput.vi) and to plot the measured data from the active region. The VI obtains K_p and l_p from these data, for each of the voltage sweeps. Note that Lambda varies. Compare the average Lambda value with that from PMOSparam.vi.

Click on Call PlotID_VSD.vi Green to bring up a plot of the active-region equation plot for -1/l_p < V_SD < V_SDmax, compared with the measured data. Lambda.vi will be used in the Mathcad analysis file.