How can I to do with LM324 offset voltage?

[mag]

lm324 offset

I want use LM324 to measure a voltage signal,all input range is 200mv,and my step resolution is 1mV,but LM324 have a 2mv typical offset voltage,And how can I to cancer so large offset voltage?

my circuit require low cost,so I can't use other advanced amp.

 

[flatulent]

offset lm324

Do you need a quad version? Try for fewer amps in a package and there will be room for offset correction pins on the package.

Another thing to try is to make the voltage to be measured zero and then subtract the output it produces in a subsequent stage.

 

[mag]

lm324 +offset

Another reason is my company have much storing lm324,So we need to use this chip.
How to cancer offset voltage?
and how to do with a great deal product's produce?

 

[batdin]

ajuste de offset lm324

Add or subtract a small voltage to/from the inactive input of the opamp.For instance,if your circuit is inverting,instead of grounding the positive input,connect it to a voltage divider that can be changed from -2 to +2 mV.Then adjust the divider till the output offset is 0.

 

[mag]

zero adjust circuit lm324

Hi,batdin
this way is very suitable for only one amp,if I use it for two order amp(the first output use as second amp's input),how can i adjust it?

 

[batdin]

lm324 circuit gain adjust

Hi,mag,
You can adjust the output of the last opamp to be zero by changing the input offset of the first one.After all they are DC coupled,right?
So it won't be a problem,trust me.

 

[mag]

lm324 gain offset

Hi,batdin,
yes,it is DC coupled,I adjust the last amp,but how about first amp's offset?

 

[mag]

lm324 offset compensation

Anyone can tell me how to consider two order amp offset?

 

[Regnum]

subtract voltage

Watching the circuit from the input, the second stage offset is affected by the first stage gain (the higher 1st stage gain, the lower 2nd stage offset contribution)
Besides compensating the offset you must check the drift (offset vs temperature) what usually is a bit harder to deal with.