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Hey guys, I'm trying to understand how to use op amps, right now I just have a battery hooked up to the non-inverting, and a virtual ground, this is a single supply cause I don't have many tools to make split supply.

The all the resistors are 220 Ohm except the left one, which I've just tossed 33,10, and some other values, but I keep getting the same as the Vin, can someone help and possibly explain how to do AC signals also, I've spent weeks trying to figure this out but can't rip YouTube.

Frostiger
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    Welcome to EE.SE. (1) If you've got 220 Ω resistors in your circuit then show them on the schematic. (2) As drawn you have the negative supply pin connected to what should be the feedback circuit to the inverting input. (3) Where did you find the circuit and why is it using positive feedback to the non-inverting input. (4) The battery voltage is missing. (5) You have no component designators (R1, R2, etc.) so it will make discussing your circuit very difficult. (6) 200 Ω is a low resistance for an op-amp to drive. It's almost 1/25 of the value shown on the schematic. Hit the edit link ... – Transistor Dec 14 '19 at 23:29
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    [Have you tried reading about operational amplifiers instead of watching videos?](https://en.wikipedia.org/wiki/Operational_amplifier) – JRE Dec 14 '19 at 23:31
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    Which op amp are you using, and what is the actual supply voltage? If you're using the ancient 741 op amp with a single +5V supply, it won't work due to its limited output voltage swing -- see https://electronics.stackexchange.com/questions/304521/reasons-not-to-use-a-741-op-amp/304522#304522 – MarkU Dec 15 '19 at 00:00
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    Recommended reading: "Opamps for Everyone" http://web.mit.edu/6.101/www/reference/op_amps_everyone.pdf – MarkU Dec 15 '19 at 00:00
  • Alright so I didn't really know how to use the circuit program, it was one I found online so if you could stop nitpicking the values, that would be great lol, that's how I have my circuit setup so the values right now I'm not worried about I'm wondering if its even right. yes I have read about it but I still can't really figure it out honestly, I've literally taken an EE class and still don't know. It's an LM358 op amp. 5V supply, 1.2V signal just from some AA battery. – Frostiger Dec 15 '19 at 07:52
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    *So if you could stop nitpicking the values* No, that's what EE is generally about - the devil is in the detail and nit-picking values can make the difference between a useless scrap and something that works. – Andy aka Dec 16 '19 at 11:23
  • I understand that, like I said it was some random program I used just to get the picture, and then said what the values were, but he was literally nitpicking the picture. – Frostiger Dec 16 '19 at 19:26
  • Corecting your diagram would be a really really really good idea. Really. People do not know what you are actually doing, and having to try to track through comments and piece together reality is not how the system is meant to work - nor how most people's brains are optimally fed. The opamp Vcc- should go to ground (of course) and the resistor from Vin- to (currently) Vcc- should go to Vout instead. THEN the gain is 2. It is ground referenced so you can expect it to amplify AC +ve half cycles and to do undefined things on negative half cycles - not a good idea in many cases. – Russell McMahon Dec 22 '19 at 00:06

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