Patent ID: 8229138

Claim:
A microphone assembly comprising: a condenser transducer element having a displaceable diaphragm and a back-plate, the displaceable diaphragm and the back-plate being arranged to form a capacitor in combination; a preamplifier circuit having an input stage comprising a P-type field effect transistor; and a microphone bias voltage source adapted to provide a DC bias voltage between the back-plate and the displaceable diaphragm, the microphone bias voltage source being integrated on an electronic or integrated semiconductor circuit die together with the input stage P-type field effect transistor; wherein the displaceable diaphragm and the back-plate are operatively connected between a source input and a gate input of the P-type field effect transistor, the back-plate being operatively connected to the gate input, and the displaceable diaphragm being operatively connected to the source input; and the displaceable diaphragm and the source input are configured to be referenced to an external power supply voltage.