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US10855253B2 · kind B2 · utility

Assignee

• Novelda AS · NO

Inventors

• Sumit Bagga · Castro Valley, US
• Kristian Granhaug · Oslo, NO

Key dates

• Filing date: Aug 17, 2017
• Grant date: Dec 1, 2020
• Expiry date: Aug 17, 2037

Classification

• Technology area (CPC H): Electricity
• CPC primary: H03H2007/013
• WIPO field: Basic communication processes
• WIPO sector: Electrical engineering

Abstract

A circuit comprising: a passive reactive component; and an active circuit, the active circuit arranged to increase the ac voltage difference across the reactive component by changing the current at an input to the reactive component and the current at an output of the reactive component by equal and opposite amounts. By increasing the current on one side of the resonant circuit and decreasing the current on the other side of the resonant circuit, the amount of current flowing through the resonant circuit is increased and thus the ac voltage difference across the inductor of the LC resonant circuit is increased. The Q of an inductor (the ratio of its imaginary to real impedance) is increased. In a filter, the improved Q provides a sharp, high rejection notch and faster pass-band to stop-band roll-off, thus improving the frequency response of the circuit.