Operational Amplifier Tutorial - Basic Non-Inverting Op Amp (Part 2)

http://www.FreedomUniversity.TV. A series of videos on the operational amplifier. For more videos on these and other technical topics. contact Professor Santiago at john@e-liteworks.com or visit the above website.

Category:

Education

Tags:

• operational amplifier
• basic op amp
• op amp
• circuit analysis
• voltage
• current
• non-inverting
• inverting

[nsmith1002]

From Wikiperdia page on operational amplifiers: "An op-amp produces an output voltage that is typically hundreds of thousands times larger than the voltage difference between its input terminals." Bit if the inputs are ALWAYS equal then there can NEVER be a difference between them to be amplified! I see other people have posted similar things here, so I know I'm not alone in not understanding this. Does anyone have a concise explanation?

[drjctu]

@nsmith1002 Output of op amp is vo=Av(vp-vn) where Av is the voltage gain of op amp, vp is the noninverting input and vn is the inverting input. Now, for an IDEAL op amp Av=very large or infinite.  Then, vp-vn=vo/Av=0 or vp=vn. This relationship vp=vn is used for analyzing an op amp. When we use this equation and ip=in=0 (ideal), then the gain of an op amp with FEEDBACK (closed-loop) is only dependent on the external feedback components since the gain is infinite in the open loop case. Dr J

[t2vietnamese]

very helpful

[drjctu]

Thanks. Dr J

[trailbuddi]

Is it good to think of an OP Amp as a "(hardware) programmable amp" perhaps?

[drjctu]

Now if you hook up a digital potentiometer for the input or feedback resistor then you can think of it as a programmable amplifier with gain. Hope this helps! Dr J

[pheeson]

Dude, you're a life saver

I have an assignment on this and our teacher can't explain shit.

[TwilightTinyTim]

Thank you Thank you Thank you!

[CheddarBob39]

Very good videos, thank you for making them. ( : My teacher is pretty good at teaching but during that class(the first one in the morning) I am usually tired as hell and am just fighting to stay awake and don't end up taking anything in.

[TrueSolarDay]

I've only watched two of your videos and both were excellent. I saved you to my favorites!

[mamaood]

cool! Dude you explained in 15 mins what my prof was mumbling about for an hour!

[paulthecoolest]

Wow you are really passionate, aren't you ,it does come through..

[TheBlacksnipper]

huh? XD

[chychyness]

mwuah.. :p

[anbadhwar]

Your videos are so helpful and time saving, Thank you drjctu.

Are you a professor at university?

[EDWARDALFONZO19]

@pheeson I feel you bro.