Flash analog-to-digital converter

摘要

A flash analog-to-digital converter comprising a bank of comparators (COMPi) with a differential output, generating a thermometric code and a bank of three-input (A,B,C) logic NOR gates (NORj) for correcting errors in said thermometric code, has enhanced immunity to noise and reduced imprecisions, especially at high conversion rates upon occurence of metastability within the comparators, by providing for a passive interface constituted by a plurality of voltage dividers (Ra-Rb), each connected between the noninverted output (out_p) of a respective comparator (COMPi) and the inverted output (out_n) of the comparator of higher order (COMPi+1) of said bank; a corresponding logic NOR gate (NORj) of said bank having a first input (A) coupled to the inverted output (out_n) of said respective comparator (COMPi-1), a second input (B) coupled to the noninverted output (out_p) of said comparator (COMPi) of higher order and a third input (C) coupled to an intermediate tap of said voltage divider (Ra-Rb). <IMAGE>