Coefficient generation for digital filters
AssigneeSynaptics Incorporated
InventorsPeijun Shan, David Sobel, Stephen L. Morein
Life of this patent
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Abstract
An example circuit includes: a filter configured to process a digital signal through at least one stage; and a coefficient generator circuit configured to generate coefficients for the at least one stage of the filter. The coefficient generator circuit includes: a lookup-table (LUT) configured to output a differential sequence; an up-sampling holder circuit configured to up-sample and hold the differential sequence to generate an up-sampled differential sequence; and an accumulator configured to integrate the up-sampled differential sequence to generate the coefficients.
Claims20
A circuit, comprising:
- a filter configured to process a digital signal through at least one stage;
- and
- a coefficient generator circuit configured to generate coefficients for the at least one stage of the filter, the coefficient generator circuit including:
- a lookup-table (LUT) configured to output a differential sequence;
- an up-sampling holder circuit configured to up-sample and hold the differential sequence to generate an up-sampled differential sequence;
- and
- an accumulator configured to integrate the up-sampled differential sequence to generate the coefficients.
A processing system, comprising:
- a plurality of receivers configured to output a plurality of analog signals;
- a plurality of analog-to-digital converters (ADCs) configured to receive the plurality of analog signals and output a plurality of digital signals;
- a plurality of finite impulse response (FIR) filters each consisting of a single multiply-accumulate (MAC) stage configured to receive a respective one of the plurality of digital signals;
- and
- a coefficient generator circuit configured to generate coefficients for the MAC stage of each of the FIR filters, the coefficient generator circuit including:
- a lookup-table (LUT) configured to output a differential sequence;
- an up-sampling holder circuit configured to up-sample and hold the differential sequence to generate an up-sampled differential sequence;
- and
- an accumulator configured to integrate the up-sampled differential sequence to generate the coefficients.
A method of generating coefficients for a filter having at least one stage, the method comprising:
- outputting, by a look-up table (LUT), values of a differential sequence;
- up-sampling and holding, by an up-sampling circuit, the values of the differential sequence to generate an up-sampled differential sequence;
- and
- integrating, by an accumulator, the up-sampled differential sequence to generate the coefficients.
Dependencies are inferred from the claim text.