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:
Oct. 20, 1992
Filed:
Nov. 04, 1991
David P Chickanosky, Jr, Ashburn, VA (US);
Joe T May, Leesburg, VA (US);
Electronic Instrumentation and Technology Inc., Sterling, VA (US);
Abstract
A Peltier cooling system for solid-state operational amplifiers reduces the bias current and allows the amplifier to perform at a level previously attained only by vacuum tube operational amplifiers. The amplifier is cooled with a Peltier junction substantially below the ambient to control the temperature very closely to a fixed value. A solid-state temperature detector is placed in thermal contact with the operational amplifier substrate. The sensor output, which is proportional to he absolute temperature of the operational amplifier, is fed to the temperature control circuitry. The control circuitry compares the sensor current with a temperature set point current, and the difference is used to control the cooler current.