Piezoresistive sensor

Claim 1

A pressure-sensing electrical circuit, comprised of a ceramic body, a source of electric current, means for electrically connecting said ceramic body with said source of electric current, and means for applying a maonmetric pressure of at least 15 pounds per square inch gauge to said ceramic body, wherein: (a)said ceramic body consists essentially of metal of metal titanate, from about 0.01 to about 5.0 atom percent (by weight of metal titanate) of an aliovalent, cationic dopant, and from about 0.01 to about 1.0 weight percent (by weight of metal titanate) of cationic counterdopant, wherein: 1. said metal titanate is selected from the group consisting of barium titanate, strontium titanate, lead titanate, and mixtures thereof; 2. the cation in said aliovalent dopant is selected from the group consisting of lanthanum, yttrium, niobium, antimony, samarium, holmium, gadolinium, and mixtures thereof; 3. the cation in said cationic counterdopant is selected from the group consisting of chromium, manganese, iron, cobalt, nickel, copper, and mixtures thereof; 4. at least about 1.1 atoms of said aliovalent dopant cation are present for each atom of counterdopant cation in said material; and 5. the particles in said sintered body have a average particle size in excess of 10 microns.