Csem Centre Suisse D'electronique Et De Microtechnique Sa

Eta Sa Fabriques D'ebauches

Csem-centre Suisse D'electronique Et De Microtechnique

Matthijs Daniel Pardoen

John F Gerrits

Vincent Von Kaenel

The control circuit includes a reference MOS transistor (24) on which preermined operating characteristics are imposed. Circuitry (21, 22, 23) is provided for comparing an operating characteristic of the transistor (24) with a reference value (V.sub.tnref) so as to produce a control voltage. This voltage, after adaptation, is applied to the transistor (24) so as to fix the threshold voltage (V.sub.th) thereof, in such a way as to maintain the operating characteristics of the transistor (24). This same threshold voltage is then imposed on all the transistors of the logic circuit with which the control circuit is associated. This control circuit makes it possible particularly to reduce the consumption of said logic circuit.

Circuit for controlling the voltages between well and sources of the

The correction circuit comprises a first quadrature phase comparator intended to receive as input two signals which are desired to be in quadrature and to have equal amplitudes. Phase adjustment means are firstly intended to correct the phase of at least one of the signal to re-establish a phase difference of 90.degree. therebetween. The correction circuit further comprises means to effectuate the sum and the difference of the signals which it receives as input and to supply the sum and the difference to a second quadrature phase comparator intended to supply as output a second error signal representative of the difference of the effective phase shift of these calculated signals and 90.degree.. The second error signal is finally supplied to amplitude adjustment means intended to correct the amplitude of at least one of said signals.

Phase difference and amplitude correction circuit

An FM receiver comprising a local oscillator (23), a heterodyning stage (24) and a demodulator stage (33). The heterodyning stage has a signal producing arrangement and a multiplier arrangement. The signal producing arrangement (25,26,27,29,30,31,32) produces n signals a.sub.1 . . . a.sub.n wherein each signal consists of a message signal modulated at the intermediate frequency of the receiver, and these signals a.sub.1 . . . a.sub.n are related by the expression

Intermediate frequency FM receiver using analog oversampling to increase

A modulator is adapted for use in a transmitter of an information transmission signal in which the information is in the form of a frequency shift keyed code. The signal is centered on a fictional carrier frequency fc, on either side of which are emitted two actual frequencies separated from the frequency fc by .DELTA.f, according to whether the binary information has a high value (+1) or a low value (-1). A first generator (1) creates carrier signals in the form of sin(2.pi.f.sub.c t) and cos(2.pi.f.sub.c t). A second generator (6) creates, as a function of the information, modulation signals of the form sin(2.pi..DELTA.ft) and cos(2.pi..DELTA.ft) which are mixed with the carrier signals. At each transition of the information, first phase shifting means (8,14) modify by k.pi. the phase of one of the modulation signals. Second phase shifting means (8,9,10,12), simultaneously with the action of the first phase shifting means and at each transition of the information, change the sign of the argument of the modulation signals. The carrier signal is thus devoid of phase jumps.

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Marin, Switzerland

Matthijs Daniel Pardoen