Electronics Tutorial - Building a Low noise signal amplifier Part 2/3 - LTspice Simulation

#63 In part of the electronics tutorial video I start working on the Low noise signal amplifier by looking at some potential op-ams to use based on their noise performance and then simulating the circuit using LTspice to see if it actually works.

Final schematic simulation:

Also in this miniseries:

Datasheets analysed:

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Music:
Creative Commons — Attribution 3.0 Unported — CC BY 3.0

[jimf]

I've been quietly lurking and watching FesZ's videos for some time now, and I have to say this guy is my absolute favorite on this subject. Thorough, showing the listener each step and how to evaluate, model, and build really quality stuff. This guy's a gem, I wish he was the guy teaching me when I learned EE back in the day.

[YoussefEl.]

I once had to design a bio instrumentation amplifier to pickup eye movement signals, which unconveniently lied in the 0hz -15 hz range, so basically in the flicker noise of almost if not all opamps. I got around it by modulating my signal to 10khz since at that frequency only thermal noise exists, filtering and then demodulating the resulting signal after all the processing. Of course from a simplicity point of view, it isn't so viable since you have to have a dedicated oscillator, two modulators, multiple filtering stages, peak detectors, etc. But it was interesting nevertheless. Keep up the videos, i really enjoy your content!

[jurajkolesar]

this design saved my butt. I am currently working on a loadcell signal amplifier that is meant to sense rapid changes in force. I am 17 right now so I don't have a lot of knowledge. this is pure gold

[mmoci]

Although I am struggling a bit with my rusty electronics knowledge and have some trouble completely understanding schematic and basic principle how filtering and amplification is achieved with your op amps circuits. But I have to write that you have excellent channel and I am looking forward for exploring it more. Subscribed... Good luck.

[realchristopher]

Bloody hell! I finally know and understand how to to interpret datasheet graph! Only for the noise part, that is. Spike is called 'flicker noise' and we do not want that of we are working at that particular frequency, in this case is 10 Hz. The steady line is called 'thermal noise' and is all right, we can use it.

[jensknudsen]

Yes, LM358's suck, but they are very affordable. It's always good to have some of them around. I use them a lot to test if prototypes are wired correctly: No smoke -> plug in the actual op amp.

[p_mouse]

Nice video again. In theory you can actually make a fourth order filter with just one opamp (the math is a bit of a thing), so also an second order bandpass (for high and low). Depending on your needs it can be beneficial to use a multiple feedback filter instead of a sallenkey.

[thaejsooriya]

I know price was a concern but did you look at any instrumentation amplifiers? We use them alot in biomedical applications where high gain and low noise is a must

[basmaal-ghali]

Thank you so much. my challenge is how to amplify a thermopile signal (10uv -1mv) using only LM358 that is available in my county nowadays because of the covid-19 pandemic! is there any way to compensate for the amplifier noise?

[hamidbesharati]

Hi .is it pussible to amplify a fast edge squre wave (rise time=30ns) with 10 Vp-p to 100 Vp-p and with rise time being less than 60ns?

[SunFinderApp]

Hi, great content. I'd like to simulate the NCV33272ADR2G but I cannot find a .model or .subckt. Do you know where to find it or how to build it?

[dimuthudissanayake]

can you explain how you calculate R and C values of the Low pass and High pass filter

[fernandohood]

I want to amplify a 1 mhz signal from a transducer in two stages of 20db. Which ic can I use?

[conamx]

why there is no phase shift in output as you are using RC filter....