Implement a sensor interface in PSoC 1

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Anonymous
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Hello everyone

   

I have some problems while I implement the circuit in PSoC 1.

   

the sensor is a three electrode sensor. the RE is a reference electrode and the voltage is set to 2.5V, the WE is working electrode and it is connected to a trans-impendance amplifier. The TIA is Implemented by configuring a CT Block. while the sensor is working, the current flows from WE to CE. The problem is, for the CE, counter electrode, I don't know how to connect it to the amplifier U2-A in PSoC 1 because there is no plain opamp in PSoC 1. Is there anyone has any idea? Thanks!

   

Best regards
Li

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ETRO_SSN583
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What is the part number of the sensor, maybe post its datasheet

   

or link to it ?

   

 

   

Regards, Dana.

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Anonymous
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hello danaaknight

   
   

the sensor is a kind of electrochemical sensor to detect the CO gas. The datasheet is:

   
   

http://www.citytech.com/PDF-Datasheets/4cf .pdf

   
   

the problem now I'm facing is how to implement the opamp U2-A and the feedback resistor capacitor R1 R2 C3 C4 in PSoC. I have tried to configure an SC block according AN2223 but it seems not right...

   
   

best regards

   
   

Li

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ETRO_SSN583
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Not having looked at your datasheet (I will shortly) I saw the following

   

circuit for a sensor that makes it clear where connections go.

   

 

   

Regards, Dana.

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ETRO_SSN583
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This might be one possibility, but I would be concerned about the
noise generated by a switched C OpAmp. However 2 pole LP filter
inherent in the double RC might be enough to allevaite this.

   

 

       

 

   

Regards, Dana.

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