AnsweredAssumed Answered

DFSDM 8 serial channels but 4 filters. Why????

Question asked by zhukov.roman on Jun 11, 2016
Latest reply on Jul 19, 2016 by zhukov.roman
I use the DFSDM in multichannel sound card USB. It is 1st time for me.
I have read that the average DFSDM has 8 channels.
When I started the project I have found that STM engineers added only 4 filters for 8 channels. It is incredible. I can't understand why? For exmaple I bought several boards and want to create 8 channel PDM MEMS mic sound card. I have introduced in MEMSIC board and found 4 channel example. I wanted to increase the number of channels. I found near the 5 bugs and correct it. So now I can create it in hardware. But during the introduction in filters I found that it is difficult to make this without integrated filters approach as it be in 4 channel example. Could you help me to understand how can I do that for 8 channels using only 4 digital filters. Or maybe I am wrong?

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