Model compatibility

[John]

I'm using Circuitmaker Pro 2000 spice simulator.

I have a JFET model which has Betatce parameter.
When I simulate I get a 'syntax unknown' error on Betatce.
Does anyone know if the following model syntax should be allowed in CM Pro
2000 ?

Thanks


..MODEL 2N3819 NJF(Beta=1.304m Betatce=-500m Rd=1 Rs=1 Lambda=2.25m
+ Vto=-3 Vtotc=-2.5m Is=33.57f
+ Isr=322.4f N=1 Nr=2 Xti=3 Alpha=311.7 Vk=243.6 Cgd=1.6p M=362.2m
+ Pb=1 Fc=500m Cgs=2.414p Kf=9.882e-003f Af=1)

 

[Mike Engelhardt]

John,

I'm using Circuitmaker Pro 2000 spice simulator.

I have a JFET model which has Betatce parameter.
When I simulate I get a 'syntax unknown' error on Betatce.

Betatce is the exponential temp. coeff of beta. If you're
at the nominal temp, you can ignore it.

Does anyone know if the following model syntax should be
allowed in CM Pro 2000 ?

.MODEL 2N3819 NJF(Beta=1.304m Betatce=-500m Rd=1 Rs=1 Lambda=2.25m
+ Vto=-3 Vtotc=-2.5m Is=33.57f
+ Isr=322.4f N=1 Nr=2 Xti=3 Alpha=311.7 Vk=243.6 Cgd=1.6p M=362.2m
+ Pb=1 Fc=500m Cgs=2.414p Kf=9.882e-003f Af=1)

That model vaguely look like something out of the libraries of
LTspice. Actually, it is missing one of the metric multipliers, so
you should update your LTspice installation. The model also includes
impact ionization. That was never part of any academic distributions
of SPICE, so it'd be a bit hit and miss if anyone involved with CM
have the expertise to implement something like that or not. BTW, it
better rewrite syntax like 9e-3f as 9.882e-18.

--Mike

 

[John]

Does LTspice have a digital Voltmeter / Ammeter? (I can see one)
I'd like to be able to measure oscillator output voltage.

Thanks,
John

 

[Mike Engelhardt]

John,

Does LTspice have a digital Voltmeter / Ammeter? (I can
see one) I'd like to be able to measure oscillator output
voltage.

You can plot any voltage by clicking on the node. Differential
voltages can be plotted by dragging the mouse between two
electrically distinct nodes. You can plot any current through
any two-terminal device by clicking on the body of the device.
Or plot the current into any pin of any 3- or more terminal
device by clicking on the pin.

Once plotted, you can take the average or rms by control-
clicking on the the plot label. Use FFT to look at frequency
components.

--Mike