A interface circuit for an acoustic transducer provided with a first detection structure and a second detection structure has: a first input and a second input; a first processing path and a second processing path coupled, respectively, to the first input and second input and supply a first processed signal and a second processed signal; and a recombination stage, which supplies a mixed signal by combining the first processed signal and the second processed signal with a respective weight that is a function of a first level value of the first processed signal. The first and second inputs receive a respective detection signal associated, respectively, to the first detection structure and to the second detection structure of the acoustic transducer; and an output stage the first processed signal, the second processed signal or the mixed signal, on the basis of a second level value of the first processed signal.