Two quadrants high speed multiplying DAC
US5128674A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 28, 1991 |
| Grant date | Jul 7, 1992 |
| Priority date | — |
| Expiry date | Mar 28, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M1/745
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A multiplying digital-to-analog converter for multiplying a bipolar input current by a digital word A having N bits a.sub.i including a current adder for adding a constant current to the bipolar input current to produce a unipolar current, a first current mirror responsive to the unipolar current for providing N binary weighted versions of the unipolar current, a second current mirror for providing binary weighted versions of the constant current, N current selection circuits respectively controlled the N bits a.sub.i for providing an output current comprising (a) the correspondingly weighted version of said unipolar current if the associated control bit is in a first state or (b) the correspondingly weighted version of the constant current if the associated control bit is in a second state, and a shifting circuit for summing the outputs of said N current selection means and for shifting the sum current to produce a bipolar output current representative of product of (a) the input bipolar current and (b) the digital word A.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.