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I want to put an exponential voltage source in Orcad / Pspice that \$V(t) = e^t\$.

I used Vexp and I don't know how to set \$V1, V2, Td1, Td2, Tc1, Tc2\$. I found an equation $$V(t)= V1+(V2-V1)((1-e^\frac{(-time-Td1)}{Tc1} )-(1-e^\frac{(-time-Td2)}{Tc2} ))$$ for $$V(t)=e^t $$ I set \$V1=0v , V2=-1v ,Tc1 =-1 ,Td1=Td2=Tc2=0\$ to so by equation I get $$V(t)= (-1)((1-e^\frac{(-time)}{-1} )-(1-e^\frac{(-time)}{0} ))=e^{time}$$ but when i put Voltage probe to find graph it doesn't show the correct result. Does anybody know how should I set the settings to get \$e^t\$ ?

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    \$\begingroup\$ Why are you using a negative time constant? Or even a null one? If you look closely, Tc1 and Tc2 are at the denominator. \$\endgroup\$ – a concerned citizen Jun 2 '20 at 11:08
  • \$\begingroup\$ to get e^t . what should I use to get that ? \$\endgroup\$ – user10578515 Jun 2 '20 at 11:10
  • \$\begingroup\$ There may be internal limiting for negative, or zero valued time constants. Better use a behavioural source for that. Though I can't be sure for PSpice, LTspice seems to allow those values and get the correct output. \$\endgroup\$ – a concerned citizen Jun 2 '20 at 11:14
  • \$\begingroup\$ Thanks but we have to use PSpice. \$\endgroup\$ – user10578515 Jun 2 '20 at 11:47

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