Abstract: An integrated control and power driving system moves a read/write head carrying arm over the surface of a disk. The integrated control and power driving system is applicable to a spindle motor, a mass storage disk drive and a voice-coil motor, for example, and includes a first chip and a second chip. The first chip integrates the output power stages driving the motors, and has an interface for outputting feedback signals representing functioning conditions of the voice-coil motor and of the spindle motor, and for receiving digital control signals of the output power stages. The second chip integrates logic drive and control circuitries of the power stages and an interface for receiving the feedback signals output by the first chip, and for transmitting to the first chip the digital control signals.

Abstract: An integrated control and power driving system moves a read/write head carrying arm over the surface of a disk. The integrated control and power driving system is applicable to a spindle motor, a mass storage disk drive and a voice-coil motor, for example, and includes a first chip and a second chip. The first chip integrates the output power stages driving the motors, and has an interface for outputting feedback signals representing functioning conditions of the voice-coil motor and of the spindle motor, and for receiving digital control signals of the output power stages.

Abstract: A frequency multiplier circuit and a controlling method thereof, which measures a period of a waveform by counting cycles of a fixed frequency timing signal, and reproduces the period by adding a number of prefixed length subperiods of the fixed frequency to the cycle count, making it as equal as possible to the period, so to minimize the reproduction error.

Abstract: A successive-approximation analog-digital converter including a logic control circuit timed by means of an external clock signal clock. The logic control circuit includes a register containing a first digital signal formed of N bits, which is the product of a first analog-digital conversion. The logic control circuit is suitable for producing a second digital signal formed of N bits through a second analog-digital conversion in N clock cycles. This analog-digital converter converts the second digital signal sent by the logic circuit to a second analog signal. A comparator compares the first analog signal with the second analog signal which has been input to the analog-digital converter.

Abstract: The present invention relates a frequency multiplier circuit and a controlling method thereof, characterised in that it measures a period of a waveform by a fixed frequency timing signal, and that it reproduces said period by approaching a number of prefixed length subperiods as equal as possible to each other so to minimise the reproduction error thanks to the interpretation of said subperiod number in the following manner m=j * 2′.

Abstract: A successive-approximation analog-digital converter including a logic control circuit timed by means of an external clock signal clock. The logic control circuit includes a register containing a first digital signal formed of N bits, which is the product of a first analog-digital conversion. The logic control circuit is suitable for producing a second digital signal formed of N bits through a second analog-digital conversion in N clock cycles. This analog-digital converter converts the second digital signal sent by the logic circuit to a second analog signal. A comparator compares the first analog signal with the second analog signal which has been input to the analog-digital converter.

Abstract: A circuit for modifying a resonant frequency of a receiver for radio frequency signals. The receiver includes an inductor connected in parallel with a capacitor. The circuit includes a switch having an additional capacitor connected between two MOS transistors, the switch being connected in parallel with the receiver to add capacitance based on a control of the MOS transistors.

Abstract: The switch of this invention has two conduction terminals and basically consists of the parallel coupling, across the two conduction terminals, of a first N-channel MOS transistor and second P-channel MOS transistor. The first MOS transistor will be conducting when the signal applied to the conduction terminals has a first polarity, and the second MOS transistor will be conducting when the signal applied to the conduction terminals has a second polarity. Advantageously, if two unidirectional conduction circuit elements are respectively connected in series with the main conduction paths of the two MOS transistors, the drain/body junctions of the latter will never be conducting regardless of the way the switch is connected.

Abstract: An integrated control and power driving system moves a read/write head carrying arm over the surface of a disk. The integrated control and power driving system is applicable to a spindle motor, a mass storage disk drive and a voice-coil motor, for example, and includes a first chip and a second chip. The first chip integrates the output power stages driving the motors, and has an interface for outputting feedback signals representing functioning conditions of the voice-coil motor and of the spindle motor, and for receiving digital control signals of the output power stages. The second chip integrates logic drive and control circuitries of the power stages and an interface for receiving the feedback signals output by the first chip, and for transmitting to the first chip the digital control signals.