An integrated circuit includes SOI-type MOS transistors on insulator, with a first well capable of being biased located under the insulator. The first wells are doped with a first conductivity type. Each first well includes, under the insulator of each transistor, a back gate region that is more heavily doped than the first well. The first wells are separated from each other by inclusion in in a second well that is also capable of being biased. The second well is doped with a second conductivity type.