Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
244 words
In an amplifier whose transmission factor is to be controlled in response to a control voltage and including means for switching the amplifier between two operating states providing mutually complementary control characteristics, an amplifier member having an inverting input, and an electronically controllable first impedance connected to receive the control voltage and to present an impedance which varies as a function of the control voltage and which determines the amplifier transmission factor, the impedance being connected, in one of the operating states, in a negative feedback path of the amplifier by the switching means, the improvement comprising: means connecting said first impedance to the output of said amplifier member; a second impedance connected to said first impedance to form therewith a series arrangement disposed between the output of said amplifier member and a point at the circuit reference potential of said amplifier; and means defining a direct current path connected to the output of said amplifier member, and wherein said switching means are connected in said amplifier for, in said one operating state, connecting the inverting input of said amplifier member to the point of connection between said first and second impedances and connecting the output of said amplifier member as the output from said amplifier, and the other operating state, connecting said direct current path in series between said amplifier member output and inverting input and connecting the point of connection between said first and second impedances as the output from said amplifier.
Claim 2
Dependent Claim
244 words
In an amplifier whose transmission factor is to be controlled in response to a control voltage and including means for switching the amplifier between two operating states providing mutually complementary control characteristics, an amplifier member having an inverting input, and an electronically controllable first impedance connected to receive the control voltage and to present an impedance which varies as a function of the control voltage and which determines the amplifier transmission factor, the impedance being connected, in one of the operating states, in a negative feedback path of the amplifier by the switching means, the improvement comprising: means connecting said first impedance to the output of said amplifier member; a second impedance connected to said first impedance to form therewith a series arrangement disposed between the output of said amplifier member and a point at the circuit reference potential of said amplifier; and means defining a direct current path connected to the output of said amplifier member, and wherein said switching means are connected in said amplifier for, in said one operating state, connecting the inverting input of said amplifier member to the point of connection between said first and second impedances and connecting the output of said amplifier member as the output from said amplifier, and the other operating state, connecting said direct current path in series between said amplifier member output and inverting input and connecting the point of connection between said first and second impedances as the output from said amplifier.
Claim 3
Dependent Claim
30 words
An arrangement as defined in claim 1 wherein said first impedance comprises a capacitor and an electronically controllable resistor connected together in parallel, and said second impedance comprises a capacitor.
Claim 4
Dependent Claim
25 words
An arrangement as defined in claim 2 wherein said amplifier member is a differential amplifier whose noninverting input receives the input signal to said amplifier.
Claim 5
Dependent Claim
25 words
An arrangement as defined in claim 1 wherein said amplifier member is a differential amplifier whose noninverting input receives the input signal to said amplifier.