PGA and Opamp for Bipolar Input

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Anonymous
Not applicable

Hi,

   

My project involves amplifying a bipolar signal and process it digital using digital lock-in amplifier.

   

I am particular interested to use PSOC 5 for my project. Can any one help me with the following:

   

1. What is the gain bandwidth of PSOC 5 Op-amp The datasheet quoted typical 8 MHz but what is the max?

   

2. How can I amplify my bipolar signal using the built in PGA?

   

3. Can I connect external components to use in conjunction of the built-in Op-Amp to amplfy my bipolar signal? If I can, how to do it?

   

 

   

Thanks a lot for your times and attention.

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4 Replies
Anonymous
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Thanks

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odissey1
Level 9
Level 9
First comment on KBA 1000 replies posted 750 replies posted
        Stargate, to get detailed assistance try posting yor project. If you have no project done yet (which seems to be the case) then describe in details WHAT you want to accomplish, not HOW. For example, from your previous posts it looks like you need to measure small amplitude, high-Z, bipolar, sine signal amplitude at about 160kHz? So let's start with your technical requirements before going into details of programming. odissey1   
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ETRO_SSN583
Level 9
Level 9
250 likes received 100 sign-ins 5 likes given

1. What is the gain bandwidth of PSOC 5 Op-amp The datasheet quoted typical 8 MHz but what is the max?

   

 

   

For a design the min spec is 6 Mhz (high power setting), thats what you can depend on. There is no max spec.

   

 

   

2. How can I amplify my bipolar signal using the built in PGA?

   

 

   

Do you need DC coupling ? If so you will have to offset the bipolar signal so it meets input

   

allowed common mode range. Here is a tool to evaluate general range of Vs in both inverting

   

and non inverting PGA configs.

   

http://masteringelectronicsdesign.com/differential-amplifier-output-common-mode-voltage-calculator/     CMR Calc IA

   

 

   

Attached some methods of offsetting signals -

   

https://www.dropbox.com/s/k1yn4m7heaixvmg/ADinput%20negative%20inputs.zip?dl=0

   

 

   

3. Can I connect external components to use in conjunction of the built-in Op-Amp to amplfy my bipolar signal? If I can, how to do it?

   

 

   

Describe what you are trying to amplify for starters, and what your goals are electrically. Do

   

you have a high CM environment you have to deal with ?

   

 

   

Regards, Dana.

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

Keep in min d closed loop BW, for a one pole compensated OpAmp, is easily

   

determined from Aol and its w3db.

   

 

   

https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0CB4QFjAAahUKEwiS...

   

 

   

Regards, Dana.

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