Abstract: An electric amplifier circuit for amplifying an output signal of a microphone comprises a supply input terminal (V10) to apply a supply potential (VDDA) for operating the electric amplifier circuit and a differential amplifier (110) having a first input terminal (E110a) for applying the output signal of the microphone (20), a second input terminal (E110b) and an output terminal (A110) for outputting an amplified output signal (OUT) of the microphone (20). A feedback path (FP) is provided between the output terminal (A110) of the differential amplifier (110) and the second input terminal (E110b) of the differential amplifier (110). A charge supplying circuit (120) is coupled to the feedback path (FP) to supply an amount of the charge to the feedback path (FP) in dependence on the supply potential (VDDA). The amount of charge supplied to the feedback path may be dependent on a change of the supply potential (VDDA).

Abstract: An electric amplifier circuit for amplifying an output signal of a microphone comprises a supply input terminal (V10) to apply a supply potential (VDDA) for operating the electric amplifier circuit and a differential amplifier (110) having a first input terminal (E110a) for applying the output signal of the microphone (20), a second input terminal (E110b) and an output terminal (A110) for outputting an amplified output signal (OUT) of the microphone (20). A feedback path (FP) is provided between the output terminal (A110) of the differential amplifier (110) and the second input terminal (E110b) of the differential amplifier (110). A charge supplying circuit (120) is coupled to the feedback path (FP) to supply an amount of the charge to the feedback path (FP) in dependence on the supply potential (VDDA). The amount of charge supplied to the feedback path may be dependent on a change of the supply potential (VDDA).

Abstract: A microphone amplifier comprises an input terminal (E100) for applying an input signal (IN), an output terminal (A100a) for outputting an output signal (OUT), and an additional output terminal (A100b) for outputting an additional output signal (VBIAS). The microphone amplifier also contains an amplifying circuit (10) for generating the output signal (OUT) by amplifying the input signal (IN), wherein the amplifying circuit (10) is connected between the input terminal (E100) and the output terminal (A100a), and a voltage generator (30) for generating the additional output signal (VBIAS). A supply voltage terminal (V30) of the voltage generator (30) is connected to the output terminal (A100a) of the microphone amplifier. Since the amplifying circuit (10) makes available a supply voltage (V) for the voltage generator (30), the microphone amplifier can be operated without a separate supply voltage terminal.

Abstract: A differential amplifier comprises a first amplifier (A1) with a signal input (Inp) and a signal output (Out1) that is fed back to a first feedback input (In1) of the first amplifier (A1) and is also connected to a first output (outp) of the differential amplifier. Furthermore, a buffer circuit (Buff) is connected to the first output (outp). A nonlinear resistor circuit (Rnl1, Rnl2) is coupled via a first output node (Vmid1) with the first output (outp) and via a second output node (Vmid2) with the buffer circuit (Buff).

Abstract: A microphone amplifier comprises an input terminal (E100) for applying an input signal (IN), an output terminal (A100a) for outputting an output signal (OUT), and an additional output terminal (A100b) for outputting an additional output signal (VBIAS). The microphone amplifier also contains an amplifying circuit (10) for generating the output signal (OUT) by amplifying the input signal (IN), wherein the amplifying circuit (10) is connected between the input terminal (E100) and the output terminal (A100a), and a voltage generator (30) for generating the additional output signal (VBIAS). A supply voltage terminal (V30) of the voltage generator (30) is connected to the output terminal (A100a) of the microphone amplifier. Since the amplifying circuit (10) makes available a supply voltage (V) for the voltage generator (30), the microphone amplifier can be operated without a separate supply voltage terminal.

Abstract: A differential amplifier comprises a first amplifier (A1) with a signal input (Inp) and a signal output (Out1) that is fed back to a first feedback input (In1) of the first amplifier (A1) and is also connected to a first output (outp) of the differential amplifier. Furthermore, a buffer circuit (Buff) is connected to the first output (outp). A nonlinear resistor circuit (Rnl1, Rnl2) is coupled via a first output node (Vmid1) with the first output (outp) and via a second output node (Vmid2) with the buffer circuit (Buff).