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Need an OP-AMP with required parameters

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patan.gova

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Hello,
Can someone help me out in finding out the OPAMP with low noise,Low current consumption and higher gain may be of 200 or above( if possible).

thanks.
 

A TL081 is good or an NE5534 is even Lower Noise.
BOTH of these require +/- supplies.

As to the 200+ GAIN, Depends somewhat as to WHAT Frequencies your using.
 

My requuired frequncies lie in the raneg of 0.5 to 3Hz.
 

For that frequency range you can make good use of the 0.1-10Hz peak-to-peak noise rating provided by most IC companies. There is always a tradeoff between noise and power consumption though. What kind of supply current/voltage are you working with?

If you want very low noise at those frequencies then using a chopper amp like the ADA4528 may be the best choice.
 

I just got a doubt as the circuit here https://embedded-lab.com/blog/?p=1671 is not using the single supply nor the coupling capacitor.
And my main question was about the OPamp suggestion of Lownoise,high gain,Lower power consumption.
Can you suggest a OPAMP with this charactersitics.
 
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I just got a doubt as the circuit here https://embedded-lab.com/blog/?p=1671 is not using the single supply nor the coupling capacitor.
It uses a single +5V supply. It does not use a coupling capacitor for the feedback ground resistor because it uses an opamp with a fairly low maximum input offset voltage of only 2mV so with a gain of 101 the worst one produces an output offset of only 202mV and they don't care because the circuit is simple.

And my main question was about the OPamp suggestion of Lownoise,high gain,Lower power consumption.
Can you suggest a OPAMP with this charactersitics.
The MCP602 opamp they use is has high gain, low power, has inputs that work at the negative supply which is 0V and has outputs that swing rail-to-rail. But it is not low noise and they do not care about noise.

I do not use low frequency low power opamps.
 

In any electronic circuit and in an opamp in particular, there are always performance tradeoffs. And shall I add, cost and availability.

That is the reason there are literally hundreds and hundreds of devices made by a dozen manufacturers.

What I do when I have to select an opamp, I create an Excell spreadsheet. In the first column I include the parameters I'm interested in for the project I'm working: noise, slew rate, power consumption, offset voltage, supply requirements, package, price, single/dual/quad, common mode range, output swing, and any other relevant parameter.
Not every project requires every parameter to be listed, for instance, a battery powered project I will definitively look for low power, but in a mains powered project I scratch that requirement off if it affects other parameters.

Now, the fun begins: I go the manufacturer's websites and look in their data selectors. I write down the parameters in the datasheet.
Unless I have very specific requirements, with 4 or 5 devices from a couple of vendors is usually enough for me to make a decision.

The point I'm trying to make is that ONLY YOU can decide which opamp is BEST for YOUR situation. And to tell you the truth, it is an educational experience.

Nowadays with the web and flash-based device selectors, it is a piece of cake finding a suitable component. Back in the 80s, one had to have stacks and stacks of databooks, and look page after page of data.
 

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