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:
Feb. 16, 1982
Filed:
Feb. 28, 1979
Daniel B Talbot, Hudson, MA (US);
DBX, Inc., Newton, MA (US);
Abstract
A multiplier circuit for controlling gain amplification of an electrical input signal responsively to a control signal comprises log conversion means for producing a log signal as a logarithmic function of the input signal, means for producing a multiplier signal as a function of the sum of the log signal and the control signal and antilog-conversion means for producing an antilog signal as an antilogarithmic function of the multiplied signal. The improvement is characterized by the log conversion means and antilog conversion means each including passive elements capable of exhibiting log-linear and antilog-linear transfer characteristics. The passive elements are preferably in the form of diode elements connected in a diode bridge.