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. 24, 1995
Filed:
Sep. 28, 1993
John W Raynes, Sandy, UT (US);
Gary Altman, Kirkland, WA (US);
Becton Dickinson and Company, Franklin Lakes, NJ (US);
Abstract
A filter for rezeroing an in-vivo pressure sensor is disclosed. The filter operates in a signal mode and a rezero mode. In the signal mode, the filter is a low pass filter which filters out noise. In the rezero mode, the filter is a low pass filter which filters out the dynamic components of an in-vivo pressure signal caused by the rezeroing of the pressure sensor. The filter is switchable between the signal and rezero modes. The filter is implemented by means of an active two pole RC filter with a Butterworth response. A circuit is provided to shorten the time in which the filter reaches its final response characteristic. Also disclosed is a method for processing an output from an in vivo pressure transducer, the output signal comprising noise, a mean pressure signal and a dynamic pressure signal. The method comprises the steps of: receiving as an input, the output signal from the pressure transducer; filtering out the noise from the received input by means of a first filter circuit; and, filtering out the dynamic pressure signal while passing the mean pressure signal by connecting a second circuit to the first filter circuit.