Browse Prior Art Database

High Speed A/D Converter

IP.com Disclosure Number: IPCOM000095935D
Original Publication Date: 1964-Oct-01
Included in the Prior Art Database: 2005-Mar-07
Document File: 2 page(s) / 44K

Publishing Venue

IBM

Related People

Betts, R: AUTHOR

Abstract

The A/D converter operates on the successive approximation principle utilizing a Goto twin circuit as the basic operative unit for each of its several stages. A Goto circuit is made up of a pair of tunnel diodes 10 and 11 serially and forwardly arranged with respect to one another. They are biased such that the magnitude and polarity of currents applied to the node N produces a potential at the node representative of that magnitude and polarity.

This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately 56% of the total text.

Page 1 of 2

High Speed A/D Converter

The A/D converter operates on the successive approximation principle utilizing a Goto twin circuit as the basic operative unit for each of its several stages. A Goto circuit is made up of a pair of tunnel diodes 10 and 11 serially and forwardly arranged with respect to one another. They are biased such that the magnitude and polarity of currents applied to the node N produces a potential at the node representative of that magnitude and polarity.

The different stages of the converter are identified as I, II, III and IV. Each stage has a complementary portion indicated by a bar designation. Thus, the complete first stage consists of two Goto circuits identified as 1 and I. The general operation is accomplished by applying steering, or controlling, currents to the nodes of the different stages via Kirchhoff adding resistance networks. These networks are so related to one another and to the analog and reference voltages as to increasingly subtract amounts of current applied to previous stages. Thus, a successive approximation is achieved with the polarities of voltages existing at the nodes of the different stages indicating the coded binary representation for that portion of the analog, input signal applied to the associated stage.

The analog voltage A is assumed to lie somewhere between reference potentials -E and +E and that the one under consideration here lies between 0 and +E. Steering currents to the twin circuit 1 therefore consist of...