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:
Jun. 24, 2003
Filed:
Jul. 31, 2000
Markus Helfenstein, Lucerne, CH;
Hans-Andrea Loeliger, Zürich, CH;
Felix Lustenberger, Cham, CH;
Felix Tarköy, Basel, CH;
Anadec GmbH, , CH;
Abstract
The method serves to add at least two values by means of a circuit. Both input values and output values are represented in differential form, either as a pair of voltages or as a pair of currents. The circuit consists of four transistors; it has a pair of current inputs for one of the input values, a pair of voltage inputs for the other input value, and a pair of current outputs for the output value. The voltage between the two voltage inputs corresponds to the first input value; the quotient of the currents through the two current inputs corresponds to the exponential of the other input value; and the quotient of the currents through the two current outputs corresponds to the exponential of the sum of the two input values. Values represented by voltages are easily transformed into current representation, and vice versa. The method is suitable for a variety of applications and the circuit can be cascaded both with copies of itself and with other circuits.