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:
Aug. 29, 1989
Filed:
Aug. 13, 1987
James R Hochschild, Plano, TX (US);
William A Severin, Allen, TX (US);
Texas Instruments Incorporated, Dallas, TX (US);
Abstract
A biquadrature switched capacitor filter having differential input/output integrator amplifiers (12,34) and switched capacitor networks (16,28,36,40). The differential outputs of one amplifier (12) are crossed and connected to the switched capacitor networks (36,40) of the other amplifier (34) to provide a negative capacitance effect. Feedforward capacitors (70,72) are switched to prevent the stage input signals (IN+, IN-) from being coupled during certain phases of a biphase nonoverlapping clock. In high-pass applications, a feedback capacitor (134, 136) makes positioning of pole and zero responses easy. Amplifier bandwidth is controlled by switched capacitors (148, 152) connected to the amplifiers during certain clock phases.