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Design Languages >> VHDL-AMS >> error "quantity exceeds blowup limit 1G (e9)"
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Message started by babuchacko on Aug 15^th, 2007, 12:11pm

Title: error "quantity exceeds blowup limit 1G (e9)"
Post by babuchacko on Aug 15^th, 2007, 12:11pm

I am creating a transistor model, in vhdl ams which consist of several simultaneous equations. At one point in the model i need to determin a quantity which takes a value of the order e16 when i calculated manually....
the simulator gives an error which says "the quantity exceeds blow up limit e9(1G)".... though it make sence for the error, i need to include that quantity which attains a value of the order e14... how can i overcome this prb.. can anyone help me......

thankyou
Babu chacko

Title: Re: error "quantity exceeds blowup limit 1G (e9)"
Post by adauto6 on Aug 15^th, 2007, 1:41pm

Maybe you have to set other tolerance for that quantity ...

Title: Re: error "quantity exceeds blowup limit 1G (e9)"
Post by babuchacko on Aug 15^th, 2007, 3:21pm

thank dude...but I have never tried changing the tolerence limit of a quantity...Do anyone know how to do that??

Title: Re: error "quantity exceeds blowup limit 1G (e9)"
Post by ACWWong on Aug 16^th, 2007, 3:48am

in verilogams you can use the nature declaration. an example is:

nature Frequency
abstol = 1K;
access = FF;
units = "Hz";
blowup = 1T;
endnature

perhaps you can lookup in your vhdlams manual something similar.

Title: Re: error "quantity exceeds blowup limit 1G (e9)"
Post by babuchacko on Aug 16^th, 2007, 6:33am

thanks for the suggestion.... will try that one....

Title: Re: error "quantity exceeds blowup limit 1G (e9)"
Post by Geoffrey_Coram on Aug 17^th, 2007, 4:45am

Strange -- are you outputting that quantity? Verilog-AMS simulators don't generally care what you do with the internal variables and only complain when terminal voltages and currents exceed blow-up limits.

You could also re-scale the quantity, ie, factor out 1e10 in the computation and put it back when you use the quantity.