A medical device (10) comprising a first circuit (12, C0) for selectively applying power to at least two electrodes applied to a human or animal subject is provided. The first circuit (12, C0) includes: a first switch (S1) electrically connected to a power terminal (PT) and a first electrode terminal (E1), the power terminal (PT) being configured to receive input power from a power source, the first electrode terminal (E1) being configured to be electrically connected to one of said at least two electrodes, the first switch (S1) being arranged in between the power terminal (PT) and the first electrode terminal (E1)； a second switch (S2) electrically connected to the power terminal (PT) and a second electrode terminal (E2), the second electrode terminal (E2) being configured to be electrically connected to another one of said at least two electrodes, the second switch (S2) being arranged in between the power terminal (PT) and the second electrode terminal (E2)； a third switch (S3) electrically connected to the first electrode terminal (E1) and a ground terminal (GT), the ground terminal (GT) being configured to be electrically connected to a ground, the third switch (S3) being arranged in between the first electrode terminal (E1) and the ground terminal (GT)； and a fourth switch (S4) electrically connected to the second electrode terminal (E2) and the ground terminal (GT), the fourth switch (S4) being arranged in between the second electrode terminal (E2) and the ground terminal (GT).
