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PSoC 5, 3 & 1 MCU

Anonymous
Not applicable

Hi all, i tried for design very low frequency like 0.05hz. But if i entered the value into filter configuration box, it displaying red sign. can any one tell me how to design filtering very low frequency. 

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1 Solution
ViDv_264506
Contributor II

Hi Sheik, 

   

use DDS with external TXCO for accuracy. Search this forum for DDS, DDS dual phase, DDS24 etc. keyword

   

Viktor

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11 Replies
ViDv_264506
Contributor II

Hi Sheik, 

   

use DDS with external TXCO for accuracy. Search this forum for DDS, DDS dual phase, DDS24 etc. keyword

   

Viktor

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Anonymous
Not applicable

Thank you bro... can you please upload the documents for it. 

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Anonymous
Not applicable

Yes i got the notes. i have to check............

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odissey1
Honored Contributor II
        Sheik, The frequency of 0.05 Hz is outside of the (official) working range of the filter component. It has been designed for audio frequency range. The limitations are 24-bit internal arithmetic and amount of samples in memory (~100). But since your frequency is very low, you can average/smooth data using CPU. If your sampling rate is high (>1-5 kHz), then pre-filter data using Filter component with cut-off frequency approx. 100 Hz, and decimate data. Now you have only about 100 samples per second, which you can easily smooth with CPU (you have to write some code for that, the simplest one is being exponential moving average filter).   
Anonymous
Not applicable

Great work you have done odissey1. I watched your YouTube video. 

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odissey1
Honored Contributor II
        Sheik, what is the source of the data? Do you have any project to show?   
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Anonymous
Not applicable

Thank you.......... Odissey1   I am going to filter the ECG signal noise. So my source of the project is ecg signal. I don't have any idea about to design low frequency filter (0.05Hz)in PSoC 5lp. can you please give me some reference for it.

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odissey1
Honored Contributor II
        ECG signal is rather fast! The whole period is about 1 sec. To have e.g. 50 points per scan, you need 50 Hz bandwidth. The issue with ECG is usually AC line noise (50/60 Hz). For that you need a notch filter.   
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Anonymous
Not applicable

If you have any example code for notch filter, could you please share that for my reference. 

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Anonymous
Not applicable

Hi, i have constructed ECG signal acquisition circuit by using discrete component. Now i am going to design the same in PSoC 5lp. so i have to design the same high and low pass filter value. I dont know how to design this using filter component of  PSoC and  i am not interested to design filter with using opamp component of PSoC and external discrete component. My another debut is PSoC ADC can convert this very low frequency of  the signal or not.

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odissey1
Honored Contributor II

Check this article on using notch filter with ECG

   

https://www.dsprelated.com/showarticle/935.php

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