Abstract: A data generator generates digital data at a sampling time interval .sub..DELTA. T (sampling frequency f.sub.s =1/.DELTA.T), and the three latest items of digital data V.sub.-1, V.sub.0, V.sub.+1 are repeatedly latched successively in three latch circuits every 3.multidot..sub..DELTA. T. A pulse response signal generator outputs unit pulse response signals of period 3.multidot..sub..DELTA. T at the time interval .multidot..sub..DELTA. T, and three multiplying-type DA converters multiply these three unit pulse response signals .phi..sub.0 (t+.sub..DELTA. T), .phi..sub.0 (t), .phi..sub.0 (t-.sub..DELTA. T) by the digital data V.sub.-1, V.sub.0, V.sub.+1, respectively, at a speed of a.multidot.f.sub.s (a times in time .sub..DELTA. T). The outputs of these multiplying-type DA converters are combined into an analog signal S.sub.A, which is delivered as an output.
Type:
Grant
Filed:
May 22, 1989
Date of Patent:
February 12, 1991
Assignees:
Ryoichi Mori, Kazuo Toraichi, Alpine Electronics Inc.
Abstract: A digital analog converter which is especially suitable for use in converting a digital audio signal into an analog audio signal includes a unit pulse response signal generator for successively generating unit pulse response signals at a predetermined time interval, a digital data generator for generating digital data at the predetermined time interval, a multiplier for multiplying a unit pulse response signal generated at a certain time by a predetermined item of the digital data, and a mixer for producing an analog signal output by combining the unit pulse response signals that have been multiplied by the digital data.