Circuit operation definition is performed in a front end environment with access to integrated circuit computer aided {HEAD ~ design tools} providing {TAIL ~ logic level} and layout level information concerning the integrated circuit 
Circuit operation definition is performed in a front end environment with access to integrated circuit computer aided { HEAD ~ design tools } providing { TAIL ~ logic level } and layout level information concerning the integrated circuit
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH