An amplifier circuit for capacitive transducers, such as miniature
electret or condenser microphones, wherein the amplifier circuit
comprises bias control means adapted to improve settling of the amplifier
circuit. Another aspect of the invention relates to a miniature condenser
microphone and a monolithic integrated circuit comprising an amplifier
circuit according to the present invention. The present invention
provides amplifier circuits of improved performance by resolving
traditionally conflicting requirements of maintaining a large input
resistance of the amplifier circuit to optimize its noise performance and
provide fast settling of the amplifier circuit.