I have 3 analog sensor which are steam , water level and gsr. I want to get mv output from 0-1023 and i should use opamp and i should use potentiometer on feedback. I decided get lm358 but i could not figure out how can i connect the sensors.
Can you give us more information on the sensors? Maybe links?
Good luck getting 0-1023 with that OpAmp (it's output is not rail to rail) without dual supply of more than +/-5V.
Ks0203 keyestudio Steam Sensor - Keyestudio Wiki.
this is my steam sensor
and this is gsr sensor.
wvmarle:
Good luck getting 0-1023 with that OpAmp (it's output is not rail to rail) without dual supply of more than +/-5V.
I am sorry to be newbie but what should i do i dont know thats why i am asking and i learned opamp at class but we did not anything practical due to covid. Can you explain what should i do ?
Why can you not connect it directly? Put 1 sensor in A0 and the other in A1? No need for an OP Amp.
umayu:
Ks0203 keyestudio Steam Sensor - Keyestudio Wiki.this is my steam sensor
Grove - GSR Sensor | Seeed Studio Wiki
and this is gsr sensor.
I am sorry to be newbie but what should i do i dont know thats why i am asking and i learned opamp at class but we did not anything practical due to covid. Can you explain what should i do ?
Read the data sheets carefully.
I don't know what you learned about OpAmps but the expression "rail to rail" I expect to be part of any basic OpAmp course, specifically the theoretical part. The output range is one of the key parameters of an OpAmp, especially if you want to use it to produce a 0-5V ouptut.
Try an MCP6002 instead. That one does give you a rail to rail output, provided it does not have to deliver any significant current. Price (in small numbers - in bulk the LM358 is of course really dirt cheap, that's probably why it's still around) is about the same but it's overall a far more capable OpAmp.
umayu:
I have 3 analog sensor which are steam , water level and gsr. I want to get mv output from 0-1023 and i should use opamp and i should use potentiometer on feedback. I decided get lm358 but i could not figure out how can i connect the sensors.
Are you saying you want to add gain using an opamp with a pot to set the gain level, so that one/some/all
of your sensors outputs are converted to the full 0..1023 scale output?
If so you'll probably need to set the mid-point too, not just the gain, in order to match the output
range of the sensor in question.
For instance if the sensor outputs 1.5V to 2.4V, you might want a gain of 5 and for 1.95V input to map to
2.5V output.
I'm working on this page which you may find useful - I'd appreciate your feedback via a PM?
This topic was automatically closed 120 days after the last reply. New replies are no longer allowed.