OVER-SAMPLING TYPE DIGITAL/ANALOG CONVERTER AND ANALOG/ DIGITAL CONVERTER

摘要

PROBLEM TO BE SOLVED: To provide an over-sampling type analog/digital converter and digital/ analog converter employing a hybrid modulator usingΔmodulation andΔΣmodulation in common that can suppress production of ringing even with an overloaded step input so as to reduce the settling time. SOLUTION: A slope forming counter 1 is provided before a hybrid modulator 2. The slope forming counter 1 generates a waveform changed stepwise with respect to an input to the hybrid modulator 2 in excess of a quantization step widthΔso as to limit a change width per one step to beΔor below. Thus, the over-sampling type digital/analog converter and analog/digital converter can prevent an overload and cause no high level ringing.