Abstract: The present invention relates to a reference voltage source in CMOS technology. The reference voltage source is based on the use of two compatible bipolar transistors (T1) and (T2) working at different current densities. A transresistance amplifier (1) connected as a negative feedback between the collectors and bases of (T1) and (T2) delivers the reference voltage (V.sub.ref). A conductor block (4) allows sufficient current to be drawn through the resistors (2) and (3) to render neglible the base current of (T1).

Abstract: The invention concerns an amplifier comprising means for compensating for the input drift voltage. During a preparation phase, the input signal of the amplifier (10) is nullified by short-circuiting the inputs (12) and (13) by means of the change-over switch (30) and the output (15) is connected to a capacitor (40) and to a secondary input (14) of the amplifier. The secondary input has a substantially lower gain than the gain relative to the main input (13), which makes it possible substantially to reduce the effect of charge injection caused by opening of the switch (60). In the amplification phase, the input (13) receives an input signal (V1) and the input drift voltage (.alpha.V) is compensated by means of the value stored in the capacitor (40).

Abstract: There is disclosed a differential amplifier which comprises bipolar transistors which may be produced using MOS technology and wherein the amplifier is particularly useful when the transistors have a poorly defined current gain. The amplifier includes a first pair of transistors having emitters connected in common and having bases forming the inputs to the differential amplifier. A second pair of transistors identical to the first pair are coupled such that the emitters and bases of said second pair are connected respectively to the emitters and bases of the first pair. The collectors of the second pair of transistors are connected to a current generator and to the input of a transconductance amplifier such that the transconductance amplifier causes the sum of the emitter currents of the first and second pairs of transistors to be controlled by the current supplied by the current generator.

Abstract: A dynamic amplifier comprises two complementary MOS transistors T1 and T2 which are connected in series, the gates G1 and G2 of which are connected to each other and to an input node by way of capacitors C1 and C2. The gate of T1 is connected to its drain by a switch means S1. The input node is connected to an input terminal and a reference voltage terminal by switch means S4 and S3 respectively and an output node between T1 and T2 is connected to an output terminal by switch means S5. The gate of T2 is connected by way of a switch means S2 to a bias voltage source.

Abstract: The invention relates to logic CMOS transistor circuits formed by at least one gate circuit, each gate circuit comprising a pair of CMOS transistor groups connected in series between the terminals of a power supply. The conductive state of both groups of transistors defines the potential of a common connection point or output node. A power dissipating means of relatively high resistance is coupled in parallel with at least a part of at least one of the said transistor groups, at least during a time interval in which both groups are in a non conductive state. This results in a quasi static behavior of the circuits according to the invention although the basic structure of the same is that of dynamic circuits.

Abstract: An autonomous electric watch comprises a receiver for picking up a magnetic or acoustic coded regulation signal delivered by a telephone set, and a control circuit automatically controlling memory circuits of the watch to regulate the frequency and/or set the time displayed in response to reception of such a signal. The regulation signal is provided by a signal generator connected to an automatic telephone reply apparatus that can be called from any subscriber telephone set, and may be combined with a pre-recorded spoken message giving instructions to the caller.