Patent ID: 7085799
Filing Date: 2006-08-01
Classification: H03H

Abstract:
1. An analog filter comprising: a first arithmetic operation section for performing moving average operation or convolution operation on individual ΔΣ-modulated discrete data to perform interpolation so that the envelope of the output waveform may be a symmetrical trapezoidal wave; and a second arithmetic operation section for performing moving average operation or convolution operation on individual discrete data of said symmetrical trapezoidal wave obtained in said first arithmetic operation section to perform interpolation, so that the envelope of the output waveform may be a quadratic curve wave passing the sample values of individual ΔΣ-modulated discrete data; characterized in that each of said first arithmetic operation section and said second arithmetic operation section has a circuit composed of a sample hold circuit of plural stages for holding a signal, an adder for adding the input and output signals of the sample hold circuit of plural stages, and a ½ divider for dividing by two the output signal of said adder, as one set of processing circuit, a plurality of sets of processing circuit being cascade connected, and said sample hold circuit of plural stages provided for said plurality of sets of processing circuit has a different number of stages.