MEMs Co-located Integrated Microphone/Earphone for Active Noise Reduction

An innovative approach for a hearing aid with active noise cancellation. A microphone that performs frequency spectrum analyzation during acoustic signal detection is proposed. The device would be low cost to manufacture and able to be integrated with a low power actuator on a similar substrate. The system is proposed with colocated driver and CMOS processing electronics. The sensing of the signal would be insensitive to amplifier variations by using a fast sampling amplifier operating in a sigma delta mode. An adaptive filter is proposed for the active noise cancellation. The sensing of all the frequencies would be performed by a single ratiometric source multiplexing the input to create a time multiplex input of the data to the signal processor.