Patent ID: 9590694
Date: 2017-03-07
CPC Classifications: H03F,H04B

Claim:
1. A transmitter for outputting an audio signal to a pair of first and second signal wires, comprising: an amplifier configured to receive an input audio signal; and first and second analog amplifier networks configured to receive an output of the amplifier, wherein the first analog amplifier network drives a first signal onto the first signal wire, and wherein the second analog amplifier network drives a second signal onto the second signal wire, each of the analog amplifier networks comprising at least one subtractor and at least one voltage doubler; wherein the first and second analog amplifier networks are configured to provide a first input resistance from the first and second signal wires in a differential mode in which the first and second signals comprise a differential version of the input audio signal, and to provide a second input resistance from an active first signal wire in a single-ended mode in which the first signal comprises a version of the input audio signal, wherein the second input resistance provided in the single ended mode is lower than the first input resistance provided in the differential mode.