An increase of half-hearing person caused by progressive aging of society in our country leads to an increase in demand for a digital hearing aid with a DSP. Because of a hard physical limit for battery capacity which stems from its wearing form, the battery life of an existing digital hearing aid comes up to only about few days. In this paper, we proposed an implementation for a bit-serial multiplier for DSP in a hearing aid with high working frequency and low power consumption. To reduce the power consumption associated with clock generation, we use a ring oscillator to dynamically generate clock pulse only in the period of calculation. In addition, we adopt the Booth encoding to reduce the number of partial products in multiplication and reduce the calculation time and power consumption associated with it. We implement the proposed multiplier and show the effectiveness of it through the comparison experiments.
