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. 10, 1981
Filed:
Apr. 19, 1979
Randall C Gray, Scottsdale, AZ (US);
W David Pace, Tempe, AZ (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
This relates to a circuit for delivering a linear voltage (V.sub.P) which is inversely proportional to the capacitance of a pressure sensitive capacitive transducer. A constant current I.sub.O is alternately switched into a reference capacitor (C.sub.R) and the transducer capacitor (C.sub.P). When the voltage across C.sub.P reaches V.sub.P, a flip-flop is toggled to direct current to C.sub.R. When the voltage across C.sub.R reaches a reference voltage (V.sub.R), the flip-flop is again toggled directing current to C.sub.P. A duty cycle detector charges integrator capacitors until the feedback voltage V.sub.P is such as to render equal the charging times of C.sub.P and C.sub.R.