Patent · US Expired

BiCOMS digital-to-analog conversion

US5508702A · kind A · utility

14Cited by
11References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 17, 1994
Grant dateApr 16, 1996
Priority date
Expiry dateJun 17, 2014

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03M1/745
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

A digital-to-analog conversion device that has one or more conversion cells, each cell coupled to a master voltage source and to a specific binary input element. The conversion cells include binary-weighted or binary-sized output transistors such that each output transistor, when called upon, delivers a unique analog output current corresponding to a particular binary signal. The master potential provided by a stable source is supplied to the control nodes of the output transistors so that the potential at those control nodes remains constant. Switching on and off of the output transistors is achieved by regulating the sources of those transistors rather than their gates. By regulating the operation of the output transistors at their sources, the present invention provides a digital-to-analog converter and a conversion method with little switching noise and minimal switching delay. The introduction of bipolar transistor devices to regulate the source and control nodes of the MOS output transistors utilizes the best characteristics of both transistor types to enhance converter monotonicity and linearity, in addition to reducing noise.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.