I am using device LT1677 in an old simulation (in LTspice), and it uses an OTA device in the model. I would like to convert it to be compatible with Qspice. I’d appreciate any help or direction provided.
Thank you,
LT1677.txt (2.3 KB)
The challenge is that, if pin8 of LTspice A-device is not connect to GND (0), it seems no equivalent way for Qspice Ã-Device to replace a A-Device.
In internet, you may locate legacy Pspice Linear Technology opamp macromodels. I can locate a LTC.lib in 2007 in this link.
courses.e-ce.uth.gr/Software/Electronics_II/ltspice/LTC.lib
This is my test with LT1677 from this 2007 library with Qspice, and compare with using LTspice with A-device in LT1677
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For a long time, I didn’t think it was possible to convert certain OTA A-device to Qspice equivalent circuit. It is actually very challenging to convert various LTspice devices into Qspice, not only OTA but also a diode with Ilimit, a switch with Vser/Ilimit/oneway, a G-source with dir/vto, etc…
However, recently, I worked out the equivalent circuit between LTspice and Qspice and was able to convert a number of circuit models into Qspice with a matlab code for this work. This is a case I couldn’t find a solution two years ago for a model containing A-devices. Use notepad++ with compare plugin, you can compare and review what need to be done for such a complex model conversion.
example.LT1677.qsch (6.2 KB)
LT1677-LTspice.txt (2.3 KB)
LT1677-Qspice-251120.txt (6.6 KB)
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