the present invention relates to a method and a device of information transfer between two circuits exchanging data via delta - sigma converters . the present invention includes coding the information in the form of at least one signal of determined frequency corresponding to an integer multiple of a frequency of the digital data samples ; mixing , at a first end of a line carrying an oversampled digital signal of the converter , the signal of determined frequency ; extracting from the mixture , at a second end of the line , the signal of determined frequency ; and decoding the corresponding information .