An all digital concha hearing aid

The paper describes an all digital concha hearing aid. The main features of this hearing aid concept are a large vent, acoustic feed-back cancellation, great flexibility by programming, a versatile equalizer, and an advanced compressor. The A/D and D/A converters have log/in characteristics and the signal processing is performed by floating point arithmetic, ensuring a large dynamic range and a signal to quantization noise ratio which is almost independent of signal level. The hearing aid contains a high speed two-way digital interface which is able to transmit measurement signals in real time. This feature provides great advantages to the fitting procedure. The main part of the hearing aid is a VLSI chip in 0.8 /spl mu/m CMOS technology, measuring 44 mm/sup 2/.<
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