Bias Circuit

P9.3 Determination of the PMOS Parameters
Procedure
• Parameters.vi sweeps output channel Chan0_out from VDD –1 to VDD + 1
(where the design bias VDD is set in the Front Panel). The gain measurement
will be made at VDD, intermediate to the sweep range. Since voltage VSD is
approximately equal to 2VSG, VSD will be relatively constant during the sweep,
as is required for a reliable measurement of Kp and Vtpo.
• Run the VI for VDD set at 6 V and 8V and verify that Vtpo is close to the
same for both VDD values. For the larger VDD (and VSD), kp (at VSD) should
be slightly larger.
• Now set VDD = 6, 7, or 8 V and the File Mode switch to Green (on) and re-
run to obtain a parameter data file. The file has RD1, RD2, kp (technically, )
and Vtpo. The Parameters are actually for M2. These will be read by the
evaluation Mathcad file.
• The parameters can be obtained with SimParam.vi from the data saved in
Parameters.vi. Paste the data from the Indicator Graph (sample, VDD = 7
V) of Parameters.vi into the Control Graph of SimParam.vi and run the VI
with the Data Mode switch set to on (Green).