Patent ID: 9668045
Date: 2017-05-30
CPC Classifications: H03F,H04R

Claim:
1. An electronic device incorporating a phantom-powered JFET gain circuit coupled to a microphone, the electronic device comprising: a microphone connected to the electronic device internally or externally; a power supply unit connected to the electronic device internally or externally, wherein the power supply unit provides a phantom power to the microphone and to the phantom-powered JFET gain circuit in the electronic device; a first JFET with its gate terminal operatively connected to a positive signal input terminal, wherein the first JFET is operatively connected to a second JFET in cascode having a positive signal output terminal for the phantom-powered JFET gain circuit; a third JFET with its gate terminal operatively connected to a negative signal input terminal, wherein the third JFET is operatively connected to a fourth JFET in cascode having a negative signal output terminal for the phantom-powered JFET gain circuit; one or more resistors operatively connected to the first JFET and the third JFET within the phantom-powered JFET gain circuit; and one or more gain-setting feed resistors external to the phantom-powered JFET gain circuit, wherein the one or more gain-setting feed resistors are operatively connected to the positive signal output terminal or the negative signal output terminal of the phantom-powered JFET gain circuit.