Interleaved cic filter
AssigneeInvenSense, Inc.
InventorStefano Cappello
Life of this patent
Estimating the term…
Abstract
An interleaved cascaded integrator-comb (“CIC”) filter receives an interleaved sensor output signal, including a plurality of digitized sensor signals at an input clock rate. An integrator of the interleaved CIC filter processes the interleaved signal to output an integrated interleaved signal. A downsampler of the interleaved CIC filter buffers portions of the integrated interleaved corresponding to a decimation rate for the interleaved signal. The portions of the signals are provided to a comb filter, which outputs a decimated interleaved signal.
Claims20
A device for processing interleaved signals, comprising:
- an integrator configured to receive an interleaved signal and output an integrated interleaved signal, wherein the interleaved signal comprises a plurality of digital signals interleaved at an input clock rate;
- a downsampler coupled to the integrator to receive the integrated interleaved signal and buffer a portion of each of the digital signals of the integrated interleaved signal;
- and
- a comb filter coupled to the downsampler to receive the portions of the digital signals and to output a decimated interleaved signal corresponding to the portions of the digital signals interleaved at clock rate corresponding the input clock rate divided by a decimation rate.
A method for processing interleaved signals, comprising:
- receiving, at an integrator, an interleaved signal comprising a plurality of digital signals interleaved at an input clock rate;
- integrating, by the integrator, the interleaved signal to generate an integrated interleaved signal;
- receiving, at a downsampler, the integrated interleaved signal;
- buffering, by the downsampler, a portion of each of the digital signals of the integrated interleaved signal;
- interleaving, at the downsampler, the portions of the digital signal at a decimated clock rate corresponding the input clock rate divided by a decimation rate;
- receiving, at a comb filter, the interleaved portions of the digital signals;
- filtering, by the comb filter, the interleaved portions of the digital signals;
- and
- outputting, from the comb filter, a decimated interleaved signal based on the filtered interleaved portions of the digital signals.
A system, comprising:
- a plurality of sensors, wherein each of the plurality sensors outputs a respective analog sensor signal;
- a multiplexer configured to generate an interleaved analog signal from the respective analog sensor signals;
- an analog-to-digital converter configured to generate an interleaved digital signal from the interleaved analog signal;
- an integrator configured to receive the interleaved digital signal and output an integrated interleaved signal, wherein the interleaved digital signal comprises a plurality of digital signals interleaved at an input clock rate;
- a downsampler coupled to the integrator to receive the integrated interleaved signal and buffer a portion of each of the digital signals of the integrated interleaved signal;
- and
- a comb filter coupled to the downsampler to receive the portions of the digital signals and to output a decimated interleaved signal corresponding to the portions of the digital signals interleaved at clock rate corresponding the input clock rate divided by a decimation rate.
Dependencies are inferred from the claim text.