How to restrict the character type value set with Min & Max value

Summary:

We have a requirement to restrict the DFF value to a minimum and maximum of 16 characters. The value that we are entering is an alphanumeric example:- TGPUNC36D18H742W

If I configure the Value Set With Minimum Value

16 

and Maximum Value 

16

I want the Application to Refuse any alpha value less than 16 and more than 16.

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