Ex parte VAN DEN BROEK et al. - Page 8

          Appeal No. 1997-4442                                                         
          Application 08/353,040                                                       

               The Examiner alternatively rejects claims 6 and 2 as                    
          unpatentable for obviousness based on de Wit and the APA that                
          trimming was well known.  The rejection, as we understand it,                
          is that it would have been obvious to trim the resistor                      
          portions in de Wit to achieve a desired resistance and TCR in                
          view the APA description of trimming a precision resistor by                 
          trimming a first path portion to a desired resistance and                    
          trimming a second path portion to a desired TCR                              
          (specification, page 1, line 25, to page 2, line 2).  We                     
          address only the rejection as stated, which does not rely on                 
          the resistor construction in the admitted prior art of Chapel.               
               Appellants argue that the prior art trimming of the                     
          adjustment portion will not work when the TCR of the resistor                
          is already greater than zero because it will simply increase                 
          the positive TCR further away from zero (Br6).  This argument                
          refers to the problem in Chapel and does not discuss why it                  
          would have been unobvious to trim the resistor in de Wit to                  
          achieve a desired resistance and TCR in view the APA.  While                 
          we might speculate that trimming would be difficult for the                  
          semiconductor resistor construction in de Wit, in the absence                
          of argument by Appellants we will not conclude that the                      

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