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Design Languages >> Verilog-AMS >> system of two equations
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Message started by littlenasboy on Feb 19^th, 2009, 1:47pm

Title: system of two equations
Post by littlenasboy on Feb 19^th, 2009, 1:47pm

I'm working on a double gate mosfet model, and I need to solve the two equations for the potential at the top and back surface of the device.

Is there a slick way to solve a system of two non-linear equations in verilog-a...like letting the circuit simulator do the work or a built in function?

Title: Re: system of two equations
Post by Geoffrey_Coram on Feb 24^th, 2009, 6:10am

The language reference manual suggests using indirect contributions, see "Multiple indirect contributions" in Section 5.6.7.1 of LRM 2.3.

V(x): ddt(V(x)) == f(V(x), V(y), V(z));
V(y): ddt(V(y)) == g(V(x), V(y), V(z));
V(z): ddt(V(z)) == h(V(x), V(y), V(z));

I've never used this in any simulator, so I don't know how well any of them do at using this feature.