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. 07, 2003
Filed:
Sep. 21, 2001
Dong-ki Min, Kyungki-do, KR;
Jong Up Jeon, Kyungki-do, KR;
Abstract
The apparatus includes a first gain adjuster, a second gain adjuster, an amplifier, a demodulator, a controller, and a change measuring unit. The first gain adjuster adjusts the gain of an input signal and outputs the gain-adjusted input signal as a first modulating signal, while the second gain adjuster adjusts the gain of an inverted input signal and outputs the gain-adjusted inverted input signal as a second modulating signal. The amplifier amplifies a modulated signal output from a junction between the first and second capacitors and outputs the amplified results. The demodulator demodulates the amplified results received from the amplifier in response to a control signal and outputs the demodulated result. The controller generates the control signal per unit period of the input signal and outputs the generated control signal to the demodulator. The change measuring unit measures the change in capacitance from the demodulated results received from the demodulator. An offset produced by parasitic capacitance is compensated without affecting the change in capacitance to be measured.