Abstract: The sampled-data band-pass filter device is based on the phenomemon of aliasing, and allows the substantially unattenuated passage of the components of an input signal at a frequency included within an interval comprised between a first frequency (f.sub.sL) and a second frequency (f.sub.sH), arranged around a third frequency (f.sub.sO), while it substantially attenuates the components of the input signal at frequencies outside said interval, and furthermore automatically performs the shift to low-frequency, around a fourth frequency (f.sub.O), of the components of the input signal which have passed without attenuation. According to the invention, the device comprises, as filter element, a sampled-data band-pass filter which employs, as sampling frequency, a fifth frequency (f.sub.s) equal to a whole submultiple of a sixth frequency (nf.sub.s) equal to the sum of the third frequency (f.sub.sO) and the fourth frequency (f.sub.

Abstract: A monolithic semiconductor device including an integrated control circuit and a pair of power transistors in a Darlington configuration integrated in the same chip solves the problem of ON-OFF switching which is prevented by the presence of parasitic transistors within the structure, these transistors preventing the correct operation of the device at saturation. The solution involves a suitable arrangement of the components in the chip, with the output transistor of the Darlington pair disposed in an intermediate position between the drive transistor of the pair and the integrated control circuit. The addition of semiconductor shields, disposed between the output transistor of the Darlington pair and the integrated control circuit further reduces the damaging effects of the parasitic transistors.