Method and apparatus for implementing binary multiplication using booth type multiplication
US4972362A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 17, 1988 |
| Grant date | Nov 20, 1990 |
| Priority date | — |
| Expiry date | Jun 17, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F2207/5442
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
In a high-speed binary multiplier circuit, the multiplicand is segmented into a series of 8-bit slices and the multiplier is modified-Booth recoded into 3-bit groups. The corresponding partial product terms are reduced in a regular array of small carry-save adder cells. Iterative use of the CSA array provides the Wallace tree function in one-seventh the chip area or number of adders of a conventional implementation. The multiplier is pipelined internally, driven by a fast, two-phase internal clock that is transparent to the user. The internal clock stops and restarts upon loading new operand and instruction data to synchronize the internal clock to the system clock. Other aspects of the invention include high-speed absolute value subtract circuitry for exponent calculations and normalizing floating point results.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.