High speed analog digital converter of the dichotomizing type

Claim 1

A high speed analog - digital converter for converting an analog voltage signal V contained in a voltage interval [V o -V ref , V o +V ref ] into a digital value of N bits, wherein the converter comprises an input stage for converting the signal V into a current is which is a function of V-V o and for producing its opposite -i, a reference current source I which is a function of V ref and its opposite -I, N-1 identical cells in series, each cell comprising two current dividers, and means for zero comparison and obtaining the absolute value, said each cell receiving the currents i e and I e and their opposites -i e and -I e and supplying currents i s and I s respectively equal to |i e |-I e :2 and I e :2 and their opposites -i s and -I s , a terminal cell comprising means for the zero comparison and for obtaining the absolute value receiving a current i e and its opposite -i e and at least one follower means, a digital coder receiving the digital signals supplied by the cells and supplying a N binary signal b 1 . . . b N representing the digitized value of the analog voltage signal V, and n connecting or linking means, in which 0≦n≦N-1, each of said connecting or linking means being positioned between two consecutive cells for transmitting the current i s supplied by one cell to the following cell, while isolating the potentials of the means for zero comparison and obtaining the absolute value of said cells.