S·P·Q·R vs LTspice®

What is the relation of the Marcus Aurelius Tool Suite, S·P·Q·R, to LTspice?

S·P·Q·R and LTspice were written by the same person, myself, Mike Engelhardt. I wrote LTspice over 20 years ago and was not the first time I took the Berkeley code to a releasable state. LTspice became overwhelmingly the most widely distributed and used analog simulator in the world, peaking at being used ~1000 times more than all other SPICE simulators combined. You might have met me because the success of LTspice led me to be on continuous lecture tour for about 10 years -- visiting a different continent almost every month. I was logging more customer face-to-face hours than any other person in the electronics industry during that period.

The simulator is what I would have written 20 years ago if, most importantly, I knew then what I know now, but also if the software technology that is used in the Marcus Aurelius simulator was available then.

The schematic capture and waveform viewer is what I would have written had today's computer hardware, particularly graphics hardware acceleration and brute bandwidth, been available back then.

S·P·Q·R is a completely independent implementation from LTspice. There simply isn't anything that I did in LTspice that I'm not now capable of doing better today. The thing about engineering is that there is always a better solution and the beauty of software is that all you have to do is type it in.1

S·P·Q·R took much more labor to develop than LTspice. The first distribution of LTspice without NDA was in October 1998, eight months after my hire date at Linear Technology Corporation. Releasing LTspice in eight months was only possible because I had been working on SPICE since 1988. S·P·Q·R has had over three years of passionate development which I hope is evident when you use it.

S·P·Q·R will eclipse the popularity that LTspice had.

LTspice Users' Conference in Osaka.
Mike Addressing the LTspice Users' Conference in Osaka, 2017.

1] I bet Marcus Aurelius Antoninus Augustus would have said that were he alive today.


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