An integrated circuit, comprising: a first circuit block (22, 122) formed in a substrate; a second circuit block (24, 124) formed in the substrate; a plurality of regions (26, 28, 30, 32, 34, 126, 128, 130, 132, 134) formed between the first circuit block and the second circuit block, the plurality of regions configured to provide noise isolation between the first circuit block and the second circuit block, the plurality of regions including a p-well block region (30, 130) having a high resistivity due to a first doping concentration of a p-type dopant low doping concentration formed in a region of the [[a]] substrate, and a first portion of a guard region (32, 132) formed in the substrate between the p-well block region and the first circuit block wherein the first portion of the guard region has a second doping concentration of a p-type dopant, a second portion of the guard region (34, 134) formed in the substrate between the p-well block region and the second circuit block wherein the second portion of the guard region has the second doping concentration, a first grounded highly doped region (26, 126) formed in the substrate between the first portion of the guard region (32, 132) and the first circuit block (22, 122) wherein the first grounded highly doped region has a third doping concentration of a p-type dopant, and a second grounded highly doped region (28, 128) formed in the substrate between the second portion of the guard region (34, 134) and the second circuit block (24, 124), wherein the second grounded highly doped region has the third doping concentration, and the second doping concentration is higher than the first doping concentration and lower than the third doping concentration. a first circuit block (22, 122) formed in a substrate; a second circuit block (24, 124) formed in the substrate; a plurality of regions (26, 28, 30, 32, 34, 126, 128, 130, 132, 134) formed between the first circuit block and the second circuit block, the plurality of regions configured to provide noise isolation between the first circuit block and the second circuit block, the plurality of regions including a p-well block region (30, 130) having a high resistivity due to a first doping concentration of a p-type dopant low doping concentration formed in a region of the [[a]] substrate, and a first portion of a guard region (32, 132) formed in the substrate between the p-well block region and the first circuit block wherein the first portion of the guard region has a second doping concentration of a p-type dopant, a second portion of the guard region (34, 134) formed in the substrate between the p-well block region and the second circuit block wherein the second portion of the guard region has the second doping concentration, a first grounded highly doped region (26, 126) formed in the substrate between the first portion of the guard region (32, 132) and the first circuit block (22, 122) wherein the first grounded highly doped region has a third doping concentration of a p-type dopant, and a second grounded highly doped region (28, 128) formed in the substrate between the second portion of the guard region (34, 134) and the second circuit block (24, 124), wherein the second grounded highly doped region has the third doping concentration, and the second doping concentration is higher than the first doping concentration and lower than the third doping concentration.