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analogue voltage supplied to PIC.. Help!

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bb

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hi, im using ADC input of PIC16F874A microcontroller. My analugue input is around 10mV. can the PIC detect this small voltage? Or the voltage signal need to be amplified before input to PIC? TQ..
 

IanP

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PICs have 10-bit ADC, so at 5V supply and 10-bit resolution the smallest voltage you can detect is in theory 4.88mV, and that is below 10mV you would like to detect.
Practically I would amplify this signal at least 10 times..
Regards,
IanP
 

batdin

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IanP is right,but you can additionally decrease the LSB by using a lower reference voltage.Refer to the datasheet to see what the minimum reference voltage can be.
(I think it's about 3V,but I'm not sure)
 

jdhar

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Unless you are in a low-noise environment - meaning you have a well-designed board, amplify the signal.
 

bangunprayogi

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I think You should amplifie that signal, altough in theory it's would be safe, but it is often in implementation that theory is not accepted. There are some factors like noise etc...
 

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