Are my calculations wrong?
Yes about as wrong as it is possible to be. It shows that you understand even less than I thought you did.
And in which way this should help me understand where I was wrong?
That 10R though will produce a 500mA load on my Uno power,
Only if the other end is connected to ground not the power input to an amplifier.
I admitted my ignorance on op-amps. I don't know how the supply line influences the circuit current, but I believe questioning myself is a good way to learn.
Figure 10 reports 5V output for 6V supply....
No it does not. Not even close. Figure 10 is the output swing you will get under different values of load on the amplifier's output. This graph only applies when you have a power supply of +15 and -15 volts.
Is it possible we are looking at two different datasheets? I've extracted Figure 9 and 10 from the datasheet I'm referring to and attached here in a small version. My Figure 10 reports "Maximum peak output voltage vs Supply voltage".
My datasheet source is Texas Instruments web site (www.ti.com
), PDF datasheet for TL082 integrated circuit.
The data sheet shows that the MINIMUM supply voltage is +5V and -5V so you can not run this amplifier directly from the 5V of the arduino because that will only give you +/- 2.5V half the minimum value you need.
I understood that a few posts back, that's why I stopped trying to provide the supply voltage from the Arduino. And yes, I understand using a voltage splitter I'm not magically multiplying my Arduino voltage, as much as I understand voltage is not absolute but ground relative.
Anyway, on my datasheet it reports a minimal supply voltage of something a little less than 4V (which I understand it means +/-4V).
That circuit you posted.
1) Why post an SVG file these are hard to view.
2) The file again is a massive picture - you have been told about this quite a few times. Now it is verging either on stupidity or malicious.
3) The circuit is total CRAP
1) What's hard to view in an SVG file? Double click and it opens up in the browser.
2) An SVG doesn't have a size, it's a vector file and as such it has the size YOU decide it to have. BTW, I've been told once and I switched to SVG files immediately and apologized: about IT I'm neither stupid nor ignorant.
3) Ok, once again that doesn't help me understand where or why and you could have used something a little less offensive, nonetheless I accept your critic and I'm ready to listen what's wrong in there.
In regards to diagrams, if you folks have a preferred size and format I'll do my best to suit your needs. Until now those massive pictures I've sent, they where max 250KB, less than a quarter of second download on modern connections. Neverthless if that's annoying you I apologize again.
You have to decide if :-
1) You want to stick to this amplifier and power it off 12V
2) You want to use a more modern amplifier and power it off the 5V from the arduino.
Until I get a different IC I don't have a choice. As I said I will switch to a LM386 as soon as I'll get my hands on it.
Because I have to power my opamp out of 12V, as we finally agreed in regards to TL082, do I need to protect the Arduino side from over voltage? If I do, as I believe, wasn't my wrong circuit doing that already?
Tell me what and I will post a diagram you can use.
This thread subject is "TL082 preamp"
but I had already bought it (5€ at the local store!)
Sorry but you have been totally ripped off.
That's why I'm not buying anything any more from that shop and I'm waiting to receive the new IC.
I might be ignorant on electronics, as I repeatedly admit, but I'm not stupid, as you repeatedly suggested above.
I've exhausted my good manners: if you want to help or explain I will appreaciate, otherwise leave me in my ignorance and find someone else to be grumpy with.