Logarithmic conversion apparatus
US4626825A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 2, 1985 |
| Grant date | Dec 2, 1986 |
| Priority date | — |
| Expiry date | Jul 2, 2005 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F7/4833
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A logarithmic converting apparatus for converting a digital binary integer into logarithmic representation and for converting logarithmic representation into digital binary integer is disclosed. The apparatus determines the bit position of a leading non-zero bit of an integer, shifts the integer such that the leading non-zero bit is the leftmost bit. A look-up table receives the shifted integer and provides a number representative of the mantissa portion of the logarithm of the shifted number. An encoder receives a Point Set Input value, a scale value for said integer, and the number of binary positions shifted and generates the exponential portion of the logarithm of the integer. For converting logarithmic representation of a number into integer representation, the apparatus has a look-up table which receives the mantissa component of the logarithmic representation and provides a first number. A decoder receives the exponential component of the logarithmic representation and a Point Set Output value, a scale value for said integer, and supplies a shifted signal. The shifted signal is supplied to a shifter along with the first number and the shifter shifts the first number by the s…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.