It is now working properly. Helmut had an LMH6321.zip demo in the files section. His model was an older one that was only slightly different, but I was able to make my model and asy files work togethe

TI supplies a seemingly straightforward spice model for its LMH6321 Unity Gain Buffer. It requires a modified opamp symbol with only 4 nodes, (IN V+ V- OUT). I edited a standard opamp symbol to have o

Problem solved: I added "OPA891" to Value 2 in both my OPA891 and OPA2891 symbols and now my sims all work using my user defined locations. Thanks to all who helped me figure this out. You spent preci

Tony and Andy, Thanks for the demo schematic which proves that the model itself is OK and that changing the line that defines the functions to match opamp2 works perfectly when the model is in the sam

It appears that the symbol is able to call the OPA891 spice model without problem. I edited the model to make the pins agree with the conventional symbols, but it won't run I used the TI model unedite

Since Version 24 came it appears that I am supposed to keep my user defined models in a different place than the factory models, However I have not yet made the switch from the file structure I had pr

TI is publishing the OPA891 model only for their TINA program. I understand there is a procedure to extract the TINA model information and make a LTSpice-compatible model. I also understand that the T

The circuit that I uploaded to the temp file area works fine with V4 set to 19V. If I change the V4 voltage to the actual voltage (20V) being used in the circuit, the analysis fails to find the DC ope

Rick, I don't know why I didn't think to check the error log! DUHH!! Thanks for your effort on my behalf!! Steve

John, I have uploaded the file in question to the temp folder. The long delay was due to problems logging on to Yahoo. Steve

Sorry, I had uploaded the wrong asc file by mistake. Please see the new file in the temp directory. I obtained the passive filter values using "Elsie". Steve

Christian Thomas wrote: "Thanks for pointing out the "mythical" qualities. It is complete rot. But it is also believable rot, which is far more dangerous." Best CT Christian, I am at a loss as to whic

Dennis wrote: "You have to use the newest version of Perl 5.8. It's available from ActiveState." With the help of Helmut's latest tutorial, I was able to use tinyperl and optimizer.pl to work in a non

Helmut, I am embarrassed that my disk search found _path.bat in the zip file you made. I thought it was somewhere in my operating system files. It is now edited and I am moving on. Steve

Helmut, I am going through the setup procedure one step at a time. I have downloaded and installed TinyPerl. I cannot figure out where to find the file _path.bat. I don't know what directory it is in,

Kendall, Thanks for the info. I will look up your articles for my next project. Steve I wrote several articles on using the solver in Excel to 'improve' circuits and export LTSpice files. The method s

(Ladies &) Gentlemen: I need to optimize a 6-pole 0.1dB Chebyshev 20Hz Hi-Pass Filter using 2 Amplifiers with 3 poles each. Sallen & Key type. I have a synthesized filter version using 3 opamps with 2

I left the "number of cycles" parameter blank - which is supposed to make the source run continuously. I also tried entering a large number in that parameter - 500 cycles, but the pulse source still q

Helmut, Thank you very much! I needed that second, experienced set of eyes to find my error. Circuit now runs fine. Please delete my circuit from the community temp file. Steve Hogan

After Mike E said "NO!" to my header pin request, I figured out a way to make wires work. Having drawn out the whole EQ now, and resolving the "Matrix is singular" errors by grounding some floating re