Hello, In the datasheet it describes coefficient test mode as below, >>>The Input to the decimating filter can be replaced with a sequence of "one impulse" and "zero" samples, where "one impulse(that is 0x4000)" is followed by (16 x M) "zeros (that is 0 × 0000)". However I got some confusing results by using test vectors provided in EVM package. 1.decimation factor=4, below is the original filter plot, below is output of coefficient test mode which has been decimated by 4, Question: how does the negative impulse response come from? 2.M=16 original filter test result of coefficient test mode output which has been decimated by 16, Additional question: how to explain the distance between response? In M=4, the distance is 64, however in M=16 the distance is 32. And maybe the root question is: what's the real input sequence in coefficient test mode? Thanks! B.R. River
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