A microphone system includes a microphone and a pre-amplification conditioning circuit configured within a housing and comprising a pair of matched JFETs configured in a differential pair with common-source configuration and, when biased, are operable to receive and amplify the differential microphone output signal. The microphone further includes a pair of BJTs configured as a complimentary feedback transistor pair with each of the pair of BJTs coupled in parallel to a corresponding one of the pair of matched JFETs, and a current sink coupled to the matched JFETs and corresponding emitter electrodes of the BJTs and operable to maintain a fixed total direct current through each of the matched JFETs and BJTs, which reduces the JFETs corresponding electrical load, reduces signal noise, and increases a maximum amplified microphone output signal level at the drains of the matched JFETs.

A first system includes first and second buck-boost amplifiers. The first amplifier is connected to a battery, includes a first inductor and a first plurality of switches connected to the first inductor, and drives first and second loads. The second amplifier is connected to the battery, includes a second inductor and a second plurality of switches connected to the second inductor, and drives the first and second loads. A controller drives the first and second plurality of switches to operate each of the first and second amplifiers in a single inductor multiple output mode. A second system includes multiple buck-boost amplifiers connected to a battery and driving respective loads. Each amplifier includes inductors and switches connected to the inductors. A controller drives the switches to utilize one or more inductors based on an amount of power used by each amplifier to drive the respective loads.

An exemplary audio enhancement system substantially eliminates latency by returning audio input signals in amplified form directly in the analog domain to the source, thereby reducing signal degradation and removing redundancy from digital and analog audio transmission and processing architectures.

An exemplary audio enhancement system substantially eliminates latency by returning audio input signals in amplified form directly in the analog domain to the source, thereby reducing signal degradation and removing redundancy from digital and analog audio transmission and processing architectures.

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.

An amplification system with an output driver stage for providing an output signal to acoustic output transducers such as speakers or haptic output devices removes signal distortion caused by output stage non-linearities by pre-distorting an input signal. The system includes the output driver stage, an input stage for receiving the input signal, and a processing block that receives the input signal and provides an output signal to the output driver stage. The processing block includes a pre-distortion circuit that applies a pre-distortion function to the input signal to generate the output signal if a signal level of the input signal is greater than a threshold amplitude, and if the signal level is less than or equal to the threshold amplitude, generates the output signal from the input signal by bypassing the pre-distortion circuit.

An aspect includes an apparatus including a first amplifier; a first field effect transistor (FET) including a first source coupled to an output of the first amplifier, and a first drain for coupling to a first load; and a first gate drive circuit including an input coupled to the output of the first amplifier and an output coupled to a first gate of the first FET. Another aspect includes a method including amplifying a first audio signal using a first audio amplifier to generate a first voltage; generating a first gate voltage based on the first voltage; applying the first gate voltage to a first gate of a first field effect transistor (FET) coupled between the first audio amplifier and a first audio transducer; and applying the first voltage to a first source of the first FET.

An aspect includes an apparatus including a first amplifier; a first field effect transistor (FET) including a first source coupled to an output of the first amplifier, and a first drain for coupling to a first load; and a first gate drive circuit including an input coupled to the output of the first amplifier and an output coupled to a first gate of the first FET. Another aspect includes a method including amplifying a first audio signal using a first audio amplifier to generate a first voltage; generating a first gate voltage based on the first voltage; applying the first gate voltage to a first gate of a first field effect transistor (FET) coupled between the first audio amplifier and a first audio transducer; and applying the first voltage to a first source of the first FET.

A modular headphone system that can afford the wearer configurable choices of hearing protection and quality sound delivery for music and programming is provided. In an embodiment, a modular headphone includes a headband and an earpiece mounted to the headband. The earpiece comprises a can comprising a speaker, the can secured to the headband. A removable and replaceable music ear cup is removably mountable to the can to overlie the speaker. A removable and replaceable hearing protection/sound amplification (HP/amp) ear cup is removably mountable to the can to overlie the speaker.

A semiconductor device includes: a first buffer at which a predetermined signal is input and that outputs a first output signal; a second buffer at which an inverted signal of the predetermined signal is input and that outputs a second output signal; and a short circuit detection circuit that, in accordance with a potential difference between the first output signal and the second output signal, outputs a short circuit evaluation signal evaluating whether or not there is a ground fault in at least one of a first terminal at an output side of the first buffer or a second terminal at an output side of the second buffer or evaluating whether or not there is a short circuit between the first terminal and the second terminal.