An insulated-gate field-effect transistor is provided with a hypoabrupt vertical dopant profile below one of its sourcedrain zones for reducing the parasitic capacitance along the pn junction between that sourcedrain zone and adjoining body material. Moreover, a common node for coupling the ground lines is provided in an insulating layer of the multi-layer substrate module. A switching circuit is disposed between an external power source and a control circuit to disconnect or connect the external power source, and includes a mechanical switch, an electronic switch and a sensing unit. The internal end includes electric vibrator motors connected to the control circuit by wires. The detection of some external event should indicate that another optimization is warranted.