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#1 Mar 13, 2017
firius2010
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Last seen: 4 years 4 months ago
Joined: 2017-03-13 23:39

Adding parameters to Optimizer

Good afternoon, I'm trying to learn how to use the optimizer advanced analysis in PSPICE for this propose, I sketch a tipical SC MOS amplifier using a MBREAKN mosfet transistor I edited the PSPICE model to included for example a different VT0, and my idea is For example use the OPTIMIZER to optimize this parameter but when I try to include this parameter in optimizer I can not find it, so my question is:

 

The parameters added in a pspice model of a component can be optimized and how do I add this to the optimizer window? In the help I read that for example the Iss of a diode can be optimized so I suppose that it is also possible for example whith W L of a transistor.

 

thank you very much.

Tue, 2017-03-14 02:59
alok
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Joined: 2016-05-10 23:49

For optimizing a SPICE model parameter - you need to first declare this model parameter as variable. It will then start showing up in Optimizable paramater list. Below is an example of NMOS model with few parameters(CBD, RDS, VTO) declared as variable

.model power_Mbreakn NMOS W=1 L=1u LEVEL=3 CBD={CBD_V} RDS={RDS_V} TT=1n VTO={VTO_V}
+  RD=0.1 RS=10E-3 RG=0.5 CGSO=1E-9 CGDO=100E-12

Simplest way to do this is by doing Edit model and modifying these parameter in text view.

You also need to declare the variables (CBD_V,  RDS_V, VTO_V) as GLOBAL parameters in your circuit/schematic.

Then these parameters should show up in optimizable paramater list as PARAM and you can set the range for these and Optimzation engine would be able to tweak these in range depending upon the optimization goal and impact of these parameters on the goal.

Tue, 2017-03-14 11:44
firius2010
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Last seen: 4 years 4 months ago
Joined: 2017-03-13 23:39

Many thanks, with your indications I could add the parameter to the optimizer and do some tests, I did not know how to define global variables then I search and found this link: http://m.eet.com/media/1179065 I say it in case anyone sees the Question can solve it also like me, I think I will be entering more often to the forum, thank you very much

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