Low-power area-efficient absolute value arithmetic unit
US5251164A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 22, 1992 |
| Grant date | Oct 5, 1993 |
| Priority date | — |
| Expiry date | May 22, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2207/5442
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A high-speed, area efficient, low-power absolute value arithmetic unit that efficiently produces the absolute value of the difference of two input operands. This arithmetic unit is adaptable to provide other output functions. Further, the arithmetic unit of the present invention may be utilized as a data path element in a high performance floating point arithmetic unit. The present invention includes a propagate and generate block, a carry-chain-and a difference multiplexer. Operands A and B are received by the absolute value arithmetic unit. The propagate and generate block converts operands A and B into propagate signals and generate signals. The carry-chain-receives propagate and generate signals and produces carry-chain-propagate signals and carry-chain-generate signals for every bit, where the most significant carry-chain-generate signal is used to indicate a borrow. The difference multiplexer receives the carry-chain-propagate and carry-chain-generate signals as well as propagate singals from the propagate-and-generate block and produces A-B and B-A. The difference multiplexer then selects either A-B or B-A to produce as an output the absolute value of A-B. The borrow signal …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.