Apparatus and method for controlling an amplification gain of an amplifier, and a digitizer circuit and microphone assembly

A microphone assembly, comprising:

• a microphone, the microphone being operable to provide a high dynamic range signal as an output;
• and
• a digitizer circuit for providing a digital representation of a high dynamic range signal, comprising:
• an input interface coupled to the output of the microphone and adapted to receive the high dynamic range signal;
• an amplifier adapted to receive the high dynamic range signal and to provide an amplified representation of the high dynamic range signal, wherein the amplifier has a controllable amplification gain;
• an analog to digital converter adapted to provide a digital representation of the amplified representation;
• and
• a controller for controlling the amplification gain of the amplifier, the controller comprising:
• a signal compressor adapted to provide a low amplitude representation using the high dynamic range signal;
• a comparator adapted to compare the signal amplitude of the low amplitude representation with a predetermined threshold;
• an output interface adapted to provide a control signal to the amplifier, the control signal being adapted to control the amplification gain of the amplifier such that the amplification gain is lowered by a scaling factor when the signal amplitude of the low amplitude representation exceeds the predetermined threshold;
• and
• a reconstructor operable to provide a digital reconstruction of the high dynamic range signal using the digital representation, the reconstructor being operable to increase the amplitude of the digital representation by the scaling factor to provide the digital reconstruction.