the load of tests is provided for the purpose of what and how can be tested in LTSpice or in practice to eval./verify your design
i just sought up anything from My Computer (can be used to detect bugs in any opamp model -- not just custom -- and many of them have these !)
____________
the image of the 4-th pass + more tests ...
+ the 2-nd pass
+ the 5-th pass , the least is the unnamed model in the prev post
Quick Apx. Spec.-s ::
GBW non-inverting configuration : 6.34 MHz
GBW inverting configuration : 6.54 MHz
SR → rising edge to non-inverting input → rising outp 6.6V/µs
SR → rising edge to inverting input → falling outp : 6.0V/µs
Min. supply -- depending on Vs and waveform : ± 2.25V (+ 4.5 V) . . . ± 7.5V (+ 15V)
Vout.max @ ±15V : ±12V
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Note! -- the AD633 test should keep all frequencies "self-homogenous" (without jitter/distortion) and having the same amplitude (←is a pass for this 741 model . . . there is not too many Spice OpAmp models passing this test ! )

The large scale image is an op Amp common mode sensitivity the more "black" the better . . . so , as it shows it's near ideal only at ±1V _ ! _

 

Wow @ci139 - I thought I was getting a hang of LTSpice... it's amazing and overwhelming all at once. I will try to grok this. I'm not sure what you're doing but it's impressive.

I've fixed the offset issue. There were a number of issues with the early build. Some of the schematics had different values of the the second stage emitter resistor 50 and 5k... 5k is correct, 50 led to a lot of burnt out transistors until I stopped and did some calculations. 50 is correct for the 20 transistor version. Did I mention a lot of burnt out transistors? Once they were identified and fixed my offset went away. My final results are not as nice as the discrete spice model but it is a working copy of a 741 that I will take to next semester's lab and do an additional test for all the opamp labs using it. I also plan on a few other discrete opamp and regulator (78xx) projects in the future.

 

Thank goodness you're using surface mount transistors or this might happen to you... like it happened to me. Now can someone get me a magnet please... I'm in the mood for folk songs. Haha just kidding. You remind me of myself when I was just a nibble not even a bit. Kudos to you.you have worked very hard...remember have fun and blow something up will ya! I mean on purpose.

 

So did you Ace it???

 

Aced the project and class... although we will be using 741 next semester I stocked up on TL072 (SOIC and DIP) and 2N2222s plus some 1A rectifiers, 2A polyfuse and bunch of other goodies. I ordered the SOT23 to 3 pin adapters... so I’ll be able to breadboard my mosfets and BJTs.

I would love to try building some of the older preamps like the API and few other coveted audio preamps.

 

Gratz Wolfie, Good Job!

 

...remember have fun and blow something up will ya! I mean on purpose.

I’m mentoring a First Robotics team and first exercise will be to pop an LED. Point being they need to learn Ohm’s law. I believe 12v is enough to decap one... it’s been a while since I’ve done that.

 

Aced the project and class... although we will be using 741 next semester I stocked up on TL072 (SOIC and DIP) and 2N2222s plus some 1A rectifiers, 2A polyfuse and bunch of other goodies. I ordered the SOT23 to 3 pin adapters... so I’ll be able to breadboard my mosfets and BJTs.

I would love to try building some of the older preamps like the API and few other coveted audio preamps.

Haha better Amy than me. Okay okay already I'll back off.. well done!