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. 07, 1977
Filed:
Apr. 14, 1976
Huel C Tucker, Centerville, OH (US);
The United States of America as represented by the Secretary of the Army, Washington, DC (US);
Abstract
An analyzer, for measuring the concentration of a particular material in a ample, has its analog voltage output connected to the analog input of a multiplying digital-to-analog converter (MDAC) whose output is connected to a voltmeter and to one input of a voltage comparator having its other input connected to a potentiometer and battery producing a reference voltage somewhat less than the known output voltage of the sample. The comparator output is connected to two gates which control the transmission of electrical pulses from a generator to the UP or DOWN inputs of a binary UP/DOWN counter, having N digital output channels connected to N digital input channels of the MDAC, in such manner that the counter counts UP, increasing the gain of the MDAC, when the MDAC output voltage is lower than the reference voltage, or counts DOWN, decreasing the MDAC gain, when the MDAC output voltage is higher than the reference voltage. After a short time, the gates are closed, to inactivate the comparator and counter, and the circuit is used, with fixed MDAC gain and fixed reference voltage, to measure the output voltage or concentration of an unknown sample. At any time, the circuit can be re-calibrated in the same manner, with a standard sample.