发明名称 Multi-rate digital filter apparatus and method for sigma-delta conversion processes
摘要 Data converter (10, 50, 150, 200) and method (250, 300) operate at variable sampling rates. Input gain stage (12) adjusts input bit stream (18) at an input bit rate (20) to produce gain adjusted bit stream (22). Integrator (14) and comb filter (16) operate on the gain adjusted bit stream (22) to produce a filtered bit stream (28) at an output bit rate (24). The gain of the integrator (14) and comb filter (16) pair varies with the sampling rates implemented. An input gain value of the input gain stage (12) adjusts to compensate for the gain of the integrator (14) and comb filter (16) pair to produce the filtered bit stream (28) within a predetermined dynamic range. DC offset stage (52) and output gain stage (54) provide further adjustment to the filtered bit stream (28). Data converters (10, 50) and method (250) convert data from a higher frequency bit rate to a lower frequency bit rate. Data converters (150, 200) and method (300) convert data from a lower frequency bit rate to a higher frequency bit rate.
申请公布号 US5731769(A) 申请公布日期 1998.03.24
申请号 US19950566639 申请日期 1995.12.04
申请人 MOTOROLA, INC. 发明人 GIRARDEAU, JR., JAMES W.;YATIM, DAVID
分类号 H03M1/12;H03H17/00;H03H17/06;H03M3/02;H03M7/32;(IPC1-7):H03M7/00 主分类号 H03M1/12
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