A circuit element includes a foam pad having a plurality of electrically conductive granules some of which are in electrical contact with each other and some of which are spaced apart from each other and an electrical path defined through the pad by the granules. The pad has a very high resistance which...http://www.google.es/patents/US7327547?utm_source=gb-gplus-sharePatente US7327547 - Circuit element and use thereof
