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#1 Jun 19, 2020
Sbrettsc
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Tolerance to Global Parameters

Is it possible to assign a DEV tolerance to a global parameter that is defined using the PARAM symbol?

Fri, 2020-06-19 17:23
retiredEE
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Parameters can be used in circuit models so I'd say yes to the DEV tolerance value.  Give it a try.
 

Fri, 2020-06-19 17:33 (Reply to #2)
Sbrettsc
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I did try to add the DEV parameter to the .PARAM statement and didn't have any luck in doing so.  

Fri, 2020-06-19 22:12
retiredEE
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This technique worked for me.  For discussion assume we have a resistor whose model is Rvar and has a tolerance (expressed as a percentage) that we want to change from the schematic via a global parameter value.
 
On the schematic create the parameter .PARAM restol=5
This sets the resistor tolerance to 5%.
 
Modify the resistor's model as follows:
.MODEL Rvar RES (R=1 DEV {0.01*restol})
 
The DEV tolerance can now be changed through the value of restol.
Mon, 2020-06-22 12:54 (Reply to #4)
Sbrettsc
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I was able to implement what I needed by using the RNDC function as part of the definition of the global variable , which will provide a random number between 0-1 for each simulation (I think using a uniform distribution).

Thank you everyone for your help.

Fri, 2023-07-14 23:51
michaelarrington
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You can declare separate variables for the target value and the tolerance, then use them in conjunction to determine whether a particular value is within the permitted range, rather than explicitly assigning a deviation tolerance to a PARAM symbol 

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Wed, 2023-07-19 22:37
andree23
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Tolerance, in the FNF context of software, refers to the acceptable range or deviation from a specified value. It is often used in scenarios where small variations in a value are considered acceptable or even expected. For example, when dealing with measurements or calculations, a tolerance value might be applied to account for small errors or uncertainties in the data.

Thu, 2023-10-19 02:44
victorpatrick
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Rather than directly assigning a deviation tolerance to a PARAM symbol, you can declare separate variables for the goal value and the tolerance, then utilize them together to evaluate whether a given value is within the allowed range.  Retro Bowl  

Thu, 2024-01-04 20:39
salmawisoky
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In the context of programming or software development, the specifics of assigning a "DEV tolerance" to a global parameter defined using the PARAM symbol would depend on the programming Run 3 .

Wed, 2024-03-13 00:06
stumble guys
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Before using the GPA Calculator, let's first understand what GPA is.

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