Successive comparison type analog/digital conversion system

Abstract

Abstract PURPOSE:To prevent errors from occurring by executing a comparing action successively from the most significant bit when a converted analog signal input is a value between first and second reference potentials and, on the other hand, starting from the comparing action of a second bit from the most significant bit when the input is the value larger or smaller than the first or second potentials. CONSTITUTION:By a reference potential generating circuit 7, a first reference potential higher than the intermediate potential of a first referring potential 2 and a second referring potential 3, and a second reference potential lower than the intermediate potential are prepared, and a size comparison 8 of an input analog signal 1 with the first reference potential and a size comparison 9 of the signal with the second reference potential are executed. When the input analog signal 1 is the value between both potentials, the comparing action is successively executed by a comparing circuit 5 from the most significant bit to a lowest bit, and when it is larger than the first reference potential or smaller than the second reference potential, the comparing action is started from the second bit from the most significant bit, and it is successively executed down to the least significant bit thereafter. Thus, the errors are not generated in a conversion characteristic.

Inventors

• 👤 Shigeru Kawada

Bibliographic Details