Eliminating noise from ADS1115

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adafruit_support_bill
 
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Re: Eliminating noise from ADS1115

Post by adafruit_support_bill »

The Arduino PID library by Brett Beauregard is very well done and has some good examples. You can use it as a plain proportional controller by just setting the Ki and Kd terms to zero.

http://playground.arduino.cc/Code/PIDLibrary
http://brettbeauregard.com/blog/2011/04 ... roduction/

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harshitengineer
 
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Re: Eliminating noise from ADS1115

Post by harshitengineer »

Hi
i have been using ads 1115 and using the differential output program with my arduino. I am reading a constant voltage from a sensor output that is 0 to 5 volt but i am getting a fluctuating output of 0-8 mv, ie if am using 0.1875 mv gain ,i am losing 42 readings of my adc output that makes adds 1115 of no use.
Believe me the multimeter reads exact non fluctuating voltage upto 1 mv accuracy.

Kindly help i am really stuck ...is ther any other adc i can use???

Harshit arora

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adafruit_support_bill
 
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Re: Eliminating noise from ADS1115

Post by adafruit_support_bill »

Believe me the multimeter reads exact non fluctuating voltage upto 1 mv accuracy.
Your multimeter is displaying the average of many samples taken over a fairly long time (500mSec is typical). That is effectively a low-pass noise filter. You can do the same with the ADS1115.

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harshitengineer
 
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Re: Eliminating noise from ADS1115

Post by harshitengineer »

Okay. But do you think the fuctuation is normal and do you there is any better solution other than averaging because this slows down my arduino readings to real unacceptable level..pls suggest what can i do at the best..
thanks

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adafruit_support_bill
 
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Re: Eliminating noise from ADS1115

Post by adafruit_support_bill »

Noise can come from many sources: 50/60Hz noise from mains power. Switching noise from the power supply, digital noise from the Arduino processor, noise from nearby flourescent lights, fans, refrigerator compressors, etc. Taming noise in sensitive analog circuits like the ADS1115 can be tricky business. Hardware or software filters are a band-aid of sorts. Keeping noise from getting into the system from the start is ideal.

There are some best practices to follow such as: Making sure you have a good clean power supply and a solid clean analog ground. Keeping your signal wires short and separated from digital circuitry. Shielding can be helpful too.

Beyond that, it is helpful to understand the nature of the noise source(s) so you can identify and suppress it at the source.. An oscilloscope is helpful there.

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HTL_Matura
 
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Re: Eliminating noise from ADS1115

Post by HTL_Matura »

Hey
I got a little problem with my ads1115.
when I set the pins to differential I always get -1 and this doesnt change in any way
I can put any voltage on the pins with no reaction

pls help me out I dont know what i can do anymore

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adafruit_support_mike
 
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Re: Eliminating noise from ADS1115

Post by adafruit_support_mike »

Post your code and a photo of your hardware.. we'll take a look and see what we can find.

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