Analog fifo memory device

Abstract

An analog FIFO memory device allowing for the suppression of the adverse effects produced by fixed pattern noise, generated inside an analog FIFO memory, on signal components. First and second analog multipliers are respectively provided on the input and output sides of the analog FIFO memory. In synchronism with the inputs/outputs of signals to/from the analog FIFO memory, a non-inverting operation and an inverting operation are alternately and repeatedly performed on the input signals and the output signals. Then, although the signal input/output characteristics of the analog FIFO memory are not changed, the fixed pattern noise generated inside the analog FIFO memory is modulated by the second analog multiplier. As a result, the spectrum of the fixed pattern noise, which originally has a lower frequency, is shifted to have a higher frequency. That is to say, since a signal band can be separated from the fixed pattern noise in terms of frequency, the fixed pattern noise can be eliminated by a low pass filter. Consequently, even when the analog FIFO memory device of the present invention is applied for delaying TV signals, the resulting TV image quality is not deteriorated.