Active Low Pass Filter in PSoC5

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Anonymous
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Anonymous
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Sorry for the double post, was having trouble with my browser. Anyway, I'm trying to design a basic active low pass filter in PSoC5 using the opamp component. Is this possible? What I would really like to know is if its possible to connect the opamp to external capacitors and resistors to make up the active filter? If so, how? I have tried and so far, it doesnt seem to be behaving as I would expect a normal opamp circuit to.

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Anonymous
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Post your circuit and hardware configuration so people here can check if there is any errors. Also please noted that the op-amp is not a split power supply op-amp.

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Anonymous
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I think your split power answer, answers my question. What I'm trying to do is have an opamp in an active low pass filter, with the ability to swing from -5V to +5V at the opamp output. Am I correct to assume that since the psoc opamp is not a split power opamp it cannot swing into the negative voltage region? Find attached the circuit, that I'm trying to achieve.

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Anonymous
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Hi Liberty,

   

 

   

Negative input cannot be applied to PSoC.

   

You'll have to level shift the input voltage so that the input voltage is greater than or equal to the ground (Vss) and lesser than or equal to power supply (Vssa).

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Anonymous
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There is a blog post made by Ganesh Raaja on using negative voltage using PSoC 1.

   

It is available at  http://www.cypress.com/?rID=50815&cache=0

   

Hope this helps.

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KishoreS_96
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Refer to this KB article on different topologies of active filters which you can construct - http://www.cypress.com/?id=4&rID=38571.

   

Regards,

   

Kishore.

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Anonymous
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 Go and download datasheet lm324 from national semi. There are some application circuits for single supply op amp applicaiton. If you can find the linear application handbook from NS, there are hips of application for op amps but not sure if that is avialable now or not.

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Anonymous
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