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As far as I know, yes, yes, and yes. I followed the original schematic and only changed the op-amp and the mosfet's. It should work the same as the original. Assuming you have read the rest of this thread, you should already know that the MOSFET's presented a problem because they are wired incorrectly in the Eagle symbol itself - not because I made a mistake. Just check the pinout of your mosfet's and "force wire" them. (ie. hook up one pin in the schematic file, then check the board file to see if it is correct. If it is not, note which pin it is, and repeat for the other pins.) I assure you that if you build it as shown, it will work. You may want to tweak the layout, but other than the mosfet problem, it works flawlessly. Good luck!!
Computerman29
Added after 11 minutes:
Here is a link to my original thread.
Go about half-way down on the first page. Download the corrected Schematic and Board files. The schematic appears to be wrong, but I assure you it will work if built as shown with the same parts.
I'm asking for the version with BC337 and BC327 (three post up). I like this one because I have all the components to bulid it. The version you linked is not the same. have I to assume the second one(linked) is the correct option?
The version a few posts up is an old version and it has errors.
Use this one...
You can use 2N3904/2N3906, BC327/BC337, or whatever general purpose transistors you have on hand. Just make sure to correct the pinout if needed!!!! I used BC640/BC639 only because I was out of 2N3904/2N3906 that I normally use.
Please note that BC640/BC639 are E-C-B, so you may need to swap C and B if you use different transistors.
About the MOSFET's, Q1 (and possibly the others) will appear to be wired incorrectly...DO NOT CHANGE IT!!!!! You can use different MOSFET's and correct the pinout like with the transistors, but I cannot guarantee it will work if you do. Several people have used different MOSFET's, but I don't think any of them worked properly (besides the original SMD N and P channel dual MOSFET). I can only say that I KNOW for a fact that it works with the ones in the schematic.
Thanks for the Eagle files, saves me re-inventing the wheel! Can you explain what you mean by the MOSFETS "appear to be wired incorrectly"? Isn't it easier to just redefine the incorrect library part?
Yes, it would, but I did not know how to edit Eagle libraries at the time this design was made. It was my first large project.
Only the P-channel's appear to be incorrect. The N-channel is OK.
If you use different MOSFET's, the problem may disappear, but check them VERY CAREFULLY to make sure!!!!!!!!!!!!!!!
In the SCHEMATIC file, disconnect all pins on one MOSFET. Connect the source. Check the BOARD file to make sure it is connected properly according to the pinout of whatever MOSFET's you use. Change as necessary (in the SCHEMATIC file). Repeat for the gate and drain. Repeat the whole process for each MOSFET. That is what I did.
Added after 8 minutes:
I have found another mistake!!!! U5-N is wired incorrectly. Here are the corrected Eagle files.
Q1 and U5-P appear to have the drain and source reversed in the schematic. Do not change it. The board is CORRECT!!!
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