An analogue-to-digital converter arrangement including a signal de-emphasis network 10.sub.I, 10.sub.Q which attenuates higher frequency analogue signals relative to lower frequency analogue signals, an A/D converter 11.sub.I, 11.sub.Q to which the de-emphasised signals are applied, and a pre-emphasis network 12.sub.I, 12.sub.Q substantially complementary to the de-emphasis network to which the digitised signals are applied.

A resonant converter arrangement comprises two resonant converters, each having a resonant circuit through which current is switched alternately in opposite directs by respective switch elements. The outputs of the two resonant converters are combined to provide an output of the arrangement which has an amplitude that is dependent upon the relative phase of the outputs of the two resonant converter. For the later purpose, switch controller controls the switch element for one of the two resonant ...

A process for the protection of converter mouths and, more particularly, to an improved process for protecting the metal and refractory lining at the mouth of a converter by applying about the converter mouth prior to operating the converter a coating which comprises a mixture of a ceramic material and sodium silicate.

The invention comprises a torque converter coupling having an input impeller, an output turbine, a power circulatory turbine, a first gearing connecting the circulatory turbine with the impeller and input shaft and the second gearing connecting the first gearing with the output shaft and a stationary part so that the circulatory turbine rotates at a speed less than that of the impeller at low output speeds and greater than that of the impeller at higher output speeds.

In a DC converter, a transformer has a first winding coupled in series with a first capacitor and a first switch between a first pair of terminals, and a second winding coupled in series with a second capacitor and an inductor between a second pair of terminals. A second switch is coupled in parallel with the series-connected first winding and first capacitor. A third switch or diode is coupled in parallel with the series-connected second winding and second capacitor. The capacitors provide ener...

The present invention provides a power converter that can be used to interface a generator that provides variable voltage at variable frequency to a supply network operating at nominally fixed voltage and nominally fixed frequency and including features that allow the power converter to remain connected to the supply network and retain control during supply network fault and transient conditions. The power converter includes a generator bridge electrically connected to the stator of the generato...

A linear A to D converter comprising a combiner means to which an input signal to be converted is fed, the input signal being combined subtractively or additively with an analogue feedback signal, and the combiner means being arranged to feed an A to D flash converter via an amplifier, which A to D flash converter is arranged to feed a D to A converter which provides the feedback signal. The D to A converter comprises a digital overflowing accumulator also arranged to drive a finite impulse resp...

An interstage amplifier for a pipelined analog to digital converter comprises an operational amplifier (50) having a first pair of capacitors (55,58), a second pair of capacitors (56,57), and switching means (59-62) connected to the capacitors and amplifier. The switching means interchanges the capacitor connections to compensate for offset in the amplifier. The arrangement provides first-order correction of capacitor mismatch.

An interstage amplifier for a pipelined analog-to-digital converter comprises an operational amplifier (50) having two balanced amplifying paths; a first pair of capacitors (55,58); a second pair of capacitors (56,57); and switching means (59-62) connected to the capacitors and said amplifier and arranged for: (i) during a first phase, enabling the first pair of capacitors (55,58) to receive a respective first sample of a first signal; (ii) during a second phase, enabling the second pair of capa...

A monostable circuit of a voltage-to-frequency converter supplies feedback pulses to balance the input signal to a first integrator. These same pulses are supplied to a second integrator where they are compared with reference pulses from a crystal-controlled clock. Any drift in the pulse-width of the feedback pulses is corrected by a control signal applied to the monostable circuit by the second integrator to vary its quasi-stable period appropriately. Thus the precision of the converter is impr...