A method of fabricating a semiconductor device includes providing a semiconductor substrate including a first landing plug and a second landing plug. According to the present invention, printed circuit pins are inserted in a circuit board from the top. The second heat exchanger is in connection with a first thermal bath during a charging cycle and with a second thermal bath during a discharging cycle. A pulldown transistor has a drain coupled to the source and drain of the MOS capacitor, a source coupled to ground, and a gate coupled to a power-supply voltage node.