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:
Jan. 28, 2014
Filed:
Jun. 13, 2012
Fazil Ahmad, Santa Clara, CA (US);
Fazil Ahmad, Santa Clara, CA (US);
Analog Devices, Inc., Norwood, MA (US);
Abstract
Apparatus and methods for notch filtering are provided. In certain implementations, an amplifier includes amplification stages for providing signal amplification, chopper circuitry for generating a chopped signal by chopping an amplified signal associated with the amplification stages at a chopping frequency, and a time-interleaved finite impulse response (FIR) notch filter for notching frequency components of the chopped signal near the chopping frequency. The time-interleaved FIR notch filter includes a plurality of FIR filters configured to sample the chopped signal at a sampling rate of about twice the chopping frequency. The FIR filters are interleaved in time to reduce sampling error. Additionally, the time-interleaved FIR notch filter includes an infinite impulse response (IIR) filter configured to average samples taken by respective ones of the FIR filters and to integrate the averaged samples to generate the time-interleaved FIR notch filter's output signal.