INTERMESHED RESISTOR NETWORK FOR ANALOG TO DIGITAL CONVERSION

摘要

INTERMESHED RESISTOR NETWORK FOR ANALOG TO DIGITAL CONVERSION In an A/D converter a resistive network produces 2n different voltage steps. The resistive network includes a coarse relatively low impedance resistive string which is subdivided into 2x coarse segments. The resistive network also includes a fine relativley high impedance resistive string comprised of one fine resistive element per each coarse segment. Each fine resistive element in the string is then subdivided into 2(n-x) fine sub-segments. In determining the value of an input voltage being sensed, all the coarse segments are used to sense which coarse segments brackets the input voltage. However, only that one fine segment, which is in parallel with the ''bracketing'' coarse resistor, is then coupled to comparator means to sense which of the fine element sub-segments brackets the input voltage.