Patent ID: 8923542

Claim:
A hearing aid comprising power supply means and at least one microphone for transforming an acoustic signal in the surroundings of a hearing aid user into an electric signal, said hearing aid further comprising a base part to be arranged outside the ear canal of the hearing aid user, said base part comprising signal processing means, an ear plug part to be arranged in the ear canal of the hearing aid user, said ear plug part comprising a receiver for transmitting sound into the ear canal, said ear plug part comprising a transducer generating a signal to be transferred to said base part, and a databus connecting said ear plug part with said base part, said databus comprising two electrical wires adapted for transmission of a signal to said receiver, and for transmission of a signal from said transducer to said base part, and said databus being adapted for providing power supply either from the base part to the ear plug part, or, from the ear plug part to the base part, through said two electrical wires, wherein at least three different states of the databus are applied in different time slots, where a first state is for transfer of power, a second state is for transmission of signal from said base part to said ear plug part, and a third state is for transmission of signal from said ear plug part to said base part.