DIGITAL FILTER DEVICE AND METHOD FOR PROCESSING SIGNAL

摘要

PROBLEM TO BE SOLVED: To attain the filtering of a one bit signal which has been sigma delta- modulated without any re-quantized distortion in a system handling a one bit signal. SOLUTION: A D-latch 3 delays a one-bit input signal from a sigma delta(ΣΔ) modulator 2. A shift register 4 alternately serially arrays the one-bit input signal from theΣΔmodulator 2 and a delayed one-bit signal from the D latch 3, at a rate which is twice as high as the rate of the above-mentioned one bit input signal, and outputs it. An analog LPF 7 converts a one-bit output signal from the shift register 4 into an analog signal.