best software for realizing analog circuits

[snishanth512]

I need to select an opamp for my project.

So, I need to diffenciate and realize the opamps.

Suggest me the best software to do it.

 

[keith1200rs]

You need to give a lot more details (which I think is why you have received no replies). If you have specific characteristics you are looking for then most manufacturers have selection guides where you can filter by noise, offset, bandwidth, power supply etc.

Keith

 

[snishanth512]

I need to detect a PPG signal from the finger.

I have decided the opamp stages .

But, I do not know to choose an opamp for the project.

Stages are current to voltage converter(input = 1 microampere (I guess)), amplifier (gain=1000), low-pass filter, high-pass filter, notch filter.

PPG signal obtained at the end of notch filter.

PPG signal frequency range is 0.9 to 2 Hz.

Since, I am working with biomedical signals opamp should overcome low frequency noises and high frequency noises effectively.

 

[keith1200rs]

I suggest you put your requirements in to the main manufacturers web sites then. Analogue Devices, Texas Instruments, Linear Technology and Maxim would be a good start. I am not sure who has the best selection guides.

You will have different requirements for different stages. The transimpedance amplifier stage will need low current and voltage noise and possibly low flicker noise as well as low bias current. With filtering stages you will need to be careful that you have a high enough bandwidth depending on the filter topology. The Texas Instruments Filter Pro software (free) gives opamp required bandwidths which may be helpful.

Keith