Electronic circuit for determination of distances between reference and data points
US6014685A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 12, 1996 |
| Grant date | Jan 11, 2000 |
| Priority date | — |
| Expiry date | Nov 12, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06G7/20
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An electronic circuit for Euclidean distance determination includes two floating gate transistors (M1, M2) connected in parallel. Voltages representing a reference point and its complement are applied to input lines (22, 24) and corresponding charges become stored on the transistors' floating gates (F1, F2). Voltages representing a data point and its complement are input to control gates (G1, G2). The transistors (M1, M2) produce a combined output current which is a quadratic or exponential function of the distance between the data and reference points according to whether the transistors are above or below threshold. The circuit (10 ) includes a diode-connected load device (M3) for deriving the square root of the output current, which is proportional to Euclidean distance when the transistors are operated above threshold. Refresh means (M44, M45) may be provided for resetting reference points. An array of circuits of the invention is employed for determination of distances between vector quantities.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.