How to measuring small DC signal by ADC in PIC or AVR?

[hongphuc118]

I want to measure the DC signal which max Volt = 2mV.
Can you show me how to do this?

 

[justinjohney]

I want to measure the DC signal which max Volt = 2mV.
Can you show me how to do this?

is your signal is regulated or nmon regulated.
if it is non regulated then use a very small ref voltage about 25mV.
but i'm not sure about the output!......:?:

 

[alexan_e]

For AVR you can't use such a low Vref, for example in mega8 the min Vref is 2v , for mega88 it is 1v

Alex

 

[papunblg]

Amplify the signal so that the range of the signal matches the input range of the ADC.

 

[dean_winchester]

I want to measure the DC signal which max Volt = 2mV.
Can you show me how to do this?

Connect a signal conditioning circuit after receiving signal. Which basically will be a buffer or a linear voltage amplifier( say an Op-amp). Then use that voltage as input to uC

 

[hongphuc118]

Connect a signal conditioning circuit after receiving signal. Which basically will be a buffer or a linear voltage amplifier( say an Op-amp). Then use that voltage as input to uC

Can you send me some examples schematic?

- - - Updated - - -

is your signal is regulated or nmon regulated.
if it is non regulated then use a very small ref voltage about 25mV.
but i'm not sure about the output!......:?:

It is regulated.

 

[dean_winchester]

connect an Op-amp in non-inverting configuration with a gain of 10 or 100 to amplify, followed by a buffer. and feed that input. be careful that the voltage does never increase the voltage (Vdd) of uC. So, i recommend use a amplifir with gain of 10.

 

[doraemon]

Hello!

For op-amps, you may consider the following document which explains
almost everything you need to know for daily use of op-amps.



Dora.