Browse Prior Art Database

Analog to Digital Conversion Device

IP.com Disclosure Number: IPCOM000094659D
Original Publication Date: 1965-Apr-01
Included in the Prior Art Database: 2005-Mar-06
Document File: 2 page(s) / 44K

Publishing Venue

IBM

Related People

Beisner, HM: AUTHOR

Abstract

An analog signal applied to input terminal 10 is converted through an array 12 of parallel-wired threshold comparators into parallel digital output signals at terminals 14...20. A feedback arrangement from higher order comparators governs the coding of the output.

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Analog to Digital Conversion Device

An analog signal applied to input terminal 10 is converted through an array 12 of parallel-wired threshold comparators into parallel digital output signals at terminals 14...20. A feedback arrangement from higher order comparators governs the coding of the output.

Each threshold comparator, e.g., 22, has a summing network, e.g., 24, wired to it. Each summing network comprises a plurality of resistors, e.g., 26, 28, 30 and 32, and there may be K such resistors. A signal available from summing network 24 at terminal 34 governs the operation of threshold comparator 22. When this signal reaches a predetermined positive voltage +Vo, threshold comparator 22 applies an output -Vo to terminal 14. Should the signal at terminal 4 be negative, threshold comparator 22 does not provide an output signal.

The remaining threshold comparators in array 12 are similar in structure and operation to that just described with two exceptions. Each higher order threshold comparator has its output fed back to all lower order summing networks. For example, threshold comparator 36 has its output fed back to summing networks 38, 40 and 24. The threshold voltage of each comparator is twice the threshold voltage of the previous stage. Thus, when an analog signal of weight eight is applied at terminal 10, only comparator 36 provides an output to terminal 20.

In another arrangement, each threshold comparator provides an equal voltage output -Vo and feedback re...