Abstract: A microphone includes a microelectromechanical system (MEMS) device responsive to sound waves or vibrations having an output coupled to a first node; a programmable gain amplifier or source follower having an input coupled to a second node, and an output for generating an analog signal, wherein the MEMS device output and the programmable gain amplifier or source follower input comprise a first nonlinear equivalent capacitance having a first capacitance-to-voltage (CV) profile; and a nonlinear capacitance component coupled to the first node, the second node, and at least one reference voltage node, wherein the nonlinear capacitance component comprises a second nonlinear equivalent capacitance having a second CV profile.

Abstract: A circuit includes a first biasing voltage source, a second biasing voltage source, a first resistor device coupled between the first biasing voltage source and a first terminal of the circuit, a second resistor device coupled between the second biasing voltage source and a second terminal of the circuit, a third resistor device coupled between the second biasing voltage source and a third terminal, a first capacitor coupled between the third terminal and ground, and an amplifier having an input coupled to the second terminal and an output coupled to a circuit output.

Abstract: A circuit includes a first biasing voltage source, a second biasing voltage source, a first resistor device coupled between the first biasing voltage source and a first terminal of the circuit, a second resistor device coupled between the second biasing voltage source and a second terminal of the circuit, a third resistor device coupled between the second biasing voltage source and a third terminal, a first capacitor coupled between the third terminal and ground, and an amplifier having an input coupled to the second terminal and an output coupled to a circuit output.

Abstract: According to an embodiment, an interface circuit includes a current replicator and a receiver. The current replicator includes a power terminal coupled to a first reference node, an output terminal configured to output a signal proportional to a signal received from a transducer, and an interface terminal coupled to the transducer. Using a single interface terminal, the current replicator may be configured to provide power to the transducer and receive output signals from the transducer. The receiver may include a first input terminal coupled to the output terminal, a second input terminal coupled to a second reference node, and a current converter circuit coupled to the first input terminal.

Abstract: In accordance with an embodiment, a two-wire microphone includes an integrated circuit. The integrated circuit includes an amplifier having a power supply connection coupled to a first pin of the integrated circuit and a reference connection coupled to a second pin of the integrated circuit, and an impedance element having a first end coupled to an output of the amplifier and a second end coupled to a first node within the integrated circuit.

Abstract: According to an embodiment, an interface circuit includes a current replicator and a receiver. The current replicator includes a power terminal coupled to a first reference node, an output terminal configured to output a signal proportional to a signal received from a transducer, and an interface terminal coupled to the transducer. Using a single interface terminal, the current replicator may be configured to provide power to the transducer and receive output signals from the transducer. The receiver may include a first input terminal coupled to the output terminal, a second input terminal coupled to a second reference node, and a current converter circuit coupled to the first input terminal.

Abstract: According to an embodiment, an interface circuit includes a current replicator and a receiver. The current replicator includes a power terminal coupled to a first reference node, an output terminal configured to output a signal proportional to a signal received from a transducer, and an interface terminal coupled to the transducer. Using a single interface terminal, the current replicator may be configured to provide power to the transducer and receive output signals from the transducer. The receiver may include a first input terminal coupled to the output terminal, a second input terminal coupled to a second reference node, and a current converter circuit coupled to the first input terminal.

Abstract: In accordance with an embodiment, a cancelation circuit includes a current mirror and a low pass filter. The current mirror includes an input terminal configured to accept an input current comprising a first noise signal, a first mirrored output and a second mirrored output. The low pass filter includes an input coupled to the first mirrored output and an output coupled to the second mirrored output. A sum of a current from the second mirrored output and a current of from the output of the low pass filter includes a phase-inverted version of the first noise signal.

Abstract: In accordance with an embodiment, a cancelation circuit includes a current mirror and a low pass filter. The current mirror includes an input terminal configured to accept an input current comprising a first noise signal, a first mirrored output and a second mirrored output. The low pass filter includes an input coupled to the first mirrored output and an output coupled to the second mirrored output. A sum of a current from the second mirrored output and a current of from the output of the low pass filter includes a phase-inverted version of the first noise signal.

Abstract: According to an embodiment, an interface circuit includes a current replicator and a receiver. The current replicator includes a power terminal coupled to a first reference node, an output terminal configured to output a signal proportional to a signal received from a transducer, and an interface terminal coupled to the transducer. Using a single interface terminal, the current replicator may be configured to provide power to the transducer and receive output signals from the transducer. The receiver may include a first input terminal coupled to the output terminal, a second input terminal coupled to a second reference node, and a current converter circuit coupled to the first input terminal.

Abstract: In accordance with an embodiment, a two-wire microphone includes an integrated circuit. The integrated circuit includes an amplifier having a power supply connection coupled to a first pin of the integrated circuit and a reference connection coupled to a second pin of the integrated circuit, and an impedance element having a first end coupled to an output of the amplifier and a second end coupled to a first node within the integrated circuit.