PSoC BLE - Opamp

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Anonymous
Not applicable

 Hello There;

   

Good Day to all!

   

In my application I'm using a PIR sensor, the output of the sensor is 1mVPP only, so I'm using 2 opamp to boost the signal to 3V and giving the 3V output to MCU to trigger. 

   

In PSoC BLE block diagram  I saw 4 programmable opamp, can I use this inbuilt opamp to boost my sensor output signal? Did any one use this opamp for similar application?? If possible , then I can reduce my BOM price and can save PCB area! 

   

Please help me by giving your suggestions!

   

 

   

Best regards

   

Kirangkr 

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4 Replies
HeLi_263931
Level 8
Level 8
100 solutions authored 50 solutions authored 25 solutions authored

The PSoC4 OpAmps have a offset voltage of 1mV. So I guess you need an external OpAmp with much better specifications, since otherwise the offset will make your measurements completely unusable.

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ETRO_SSN583
Level 9
Level 9
250 likes received 100 sign-ins 5 likes given

Consider adpating CDS to your problem -

   

 

   

http://www.cypress.com/?rID=49159     AN66444 - PSoC® 3 and PSoC 5LP Correlated Double Sampling to Reduce Offset, Drift, and Low Frequency Noise

   

http://www.cypress.com/?rID=2894     AN2226 - PSoC® 1 - Using Correlated Double Sampling to Reduce Offset, Drift, and Low Frequency Noise

   

         

   

http://www.cypress.com/?rID=2813     AN2099 - PSoC® 1, PSoC 3, PSoC 4, and PSoC 5LP - Single-Pole Infinite Impulse Response (IIR) Filters

   

 

   

Here is a solution using an OpAmp with much more offset, which may be irrelative

   

to the design depending on how you are using PIR -

   

 

   

    

   

          http://www.maxmcarter.com/annunciator/PIR_sensor_rebuild.html

   

 

   

Regards, Dana

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Anonymous
Not applicable

 Hello Dana;

   

Good Day to you!

   

 

   

Thnak you so much! The links are really useful, thanks for your support! 

   

 

   

Regards

   

Kirangkr

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ETRO_SSN583
Level 9
Level 9
250 likes received 100 sign-ins 5 likes given

Glad to have been of assistance.

   

 

   

Regards, Dana.

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