How to used auto tabbing in Dialog box ?

How to used auto tabbing in Dialog box ?

Hello everyone.

     I am newly on jquery and javascript. I have been working on the dialog box.  when customer click on the link the dialog box open and display some data this used json. and on the dialog box has text box SSN for customer to type in SSN number  and submit button. everything work great but i have only one problem that i  can't figure out how to make it work, my boss wanted when customer filled in SSN number that allowed 9 digits when typing the last digits they wanted auto tabbing to the next field or button in my case without using any tab key or mouse. I've trying to used    $("input").autotab(); and added  
 <script src="@RLISDev.Utilities.appendVersionToJSInclude(Url.CdnContent("~/Scripts/jquery.autotab.js"))" type="text/javascript"></script>

but not thing work its worse my dialog box even not work at all.