Abstract: A differential input stage for an operational amplifier includes a transistor pair differentially connected and supplied with tail current through a series resistor. The tail current is supplied by a pair of current amplifiers having their outputs coupled to the tail current resistor. The current amplifier inputs are coupled to the bases of the input transistor pair so that they are differentially driven. If the tail current resistor is properly selected the differential output current is a linear function of the differential input voltage. A clamp is provided for the differential input at some relatively large input signal voltage.

Abstract: A loop, formed in a single suspended strand of a photo-elastic material, serves as an inertia mass that is rotatable about the axis of the suspended strand. The angular displacement of the loop, due to an accelerating force, is measured as a function of the change in polarization angle of a radiant beam passing through the strand.

Abstract: In order to diminish the risk of oscillation of a broad-band amplifier 20 MHz without considerably reducing the product gain x bandwidth, this amplifier comprises a differential stage T1, T2, T3, T4, a follower stage T5, T6, two common mode feed-back braches T8, T9, T5 on the one hand, T11, T12, T10, on the other hand, and compensation capacitors C1, C2 that are unbalanced, C2 higher than C1, between the supply terminal B and each of the outputs S1, S2 of the differential stage.