Patent · US Expired

Hierarchical carry-select, three-input saturation

US5889689A · kind A · utility

22Cited by
4References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 8, 1997
Grant dateMar 30, 1999
Priority date
Expiry dateSep 8, 2017

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F7/49921
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

There is disclosed a first adder subtractor combines the largest positive number or largest negative number capable of being represented by the number of bits in the datapath, as determined by the sign of an input to a second adder with a first input to generate a first potential sum. A second adder operating in parallel with the first adder combines first, second and third inputs to generate a second potential sum. An overflow detector combines the first and second inputs of the second adder to determine if there is an overflow. If an overflow is not present, a multiplexer selects the output of the second adder as the output to be saturated. If an overflow is present, the multiplexer selects the output from the first adder as the output to be saturated.

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