Abstract: The present invention teaches a variety of transconductance circuits formed having two or more class AB transconductor amplifiers coupled in parallel. The class AB transconductor amplifiers have non-linear voltage to current transfer functions and are each designed with an offset chosen such that the combination of the individual nonlinear transfer functions achieve a more linear transconductance circuit.

Abstract: The present invention teaches output stages having distortion performance improved relative to prior art class-AB output stage distortion performance. The general concept is to constantly bias the feed-forward circuitry of the output stage into a low-distortion operating state. This can be done through several different methods, each of which has its own particular circuit requirements. For example, in one embodiment the bias circuitry generates a near constant bias current suitable for forcing the feed-forward circuitry into a low-distortion operating state regardless of the output stage output value.

Abstract: The present invention teaches a variety of output stages, buffer circuits, and power amplifiers as well as methods for buffering electrical signals. According to one embodiment of the present invention, an output stage includes an input, an output, an error stage coupled between the input and the output and responsive to a difference between an input signal present on the input and an output signal present on the output, the error stage being operative to generate a current control signal related to the difference between the input signal and the output signal, a current mirror coupled to the error stage and responsive to the current control signal to generate a demand driven current signal related to a magnitude of the current control signal, and an amplification stage coupled between the input and the output.

Abstract: In accordance with the objectives of the present invention, a variety of apparatus and methods for amplifying an electrical signal are disclosed. According to one embodiment of the present invention, a dual-output stage amplifier includes an amplifier stage having an input and an output, a first output stage having an input and an output, a second output stage having an input and an output and an error stage having an input and an output. The first output stage output is coupled with the output of the amplifier stage and responsive to the amplifier stage. If the first output stage output is coupled to an output load, the first output stage is capable of providing an output current to the output load such that a first output voltage related to an input voltage at the input of the amplifier stage is maintained across the output load. In turn, the second output stage input is coupled with the output of the amplifier stage and in parallel with the first output stage.