The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 12, 1991
Filed:
Feb. 26, 1990
Ivan T Chan, Kanata, CA;
Russell W Brown, Nepean, CA;
Digital Equipment Corporation of Canada, Ltd., Kanata, CA;
Abstract
Circuitry and method for generating electrical currents representative of an exponential function of an input current. The circuit includes an input diode chain and an output diode chain. Each of the diodes in the input diode chain has an input current passing therethrough. The input current is produced by an input current source connected in sources with the diode below the cathode of the diode. A voltage driving circuit drives a voltage drop across the output diode chain that has a predetermined relationship to the voltage drop across the input diode chain. The voltage drop across the output diode chain results in a current through the output diode chain. The number of diodes in the output diode chain is preselected relative to the number of diodes in the input diode chain such that the current through the output diode chain is representative of an exponential function of the input current or currents.