Semiconductor device

A semiconductor device comprising:

• a substrate body of a first conductivity-type;
• a first well region of a second conductivity-type provided in the substrate body and provided with a high-side circuit;
• a first voltage blocking region of the second conductivity-type provided around the first well region and having a lower impurity concentration than the first well region;
• a contact region of the second conductivity-type provided at an upper part of the first well region or the first voltage blocking region and having a higher impurity concentration than the first well region;
• a second voltage blocking region of the first conductivity-type provided on an outer circumferential side of the first voltage blocking region so as to be in contact with the first voltage blocking region;
• a first isolation region of the first conductivity-type provided to electrically isolate, from the first well region, an opposed part of the first voltage blocking region opposed to a low-side circuit provided on an outer circumferential side of the second voltage blocking region;
• and
• a level shifter provided to execute a signal transmission between the low-side circuit and the high-side circuit.