Re: [Help-gnucap] Zener Diodes?

[mcmahill]

On Sun, 6 Oct 2002, Hugo van der Merwe wrote:

> I need to simulate a Zener diode, I'd expect from the documentation of
> the D device, that I need to set:
> 
> BV = x
> Reverse breakdown voltage. (Default = $\infty$.) SPICE parameter
> accepted but not implemented.
> 
> It not being implemented means that I cannot use Gnucap to simulate
> Zener's?
> 

you can come up with a bit of a hack depending on the accuracy you need.
one approach is to put a diode in parallel with a second diode that has a
voltage source in series with it.  The first diode models the zener when
forward biases and the second (which is connected in the opposite
polarity) turns on after you overcome the offset incured by the voltage
source.  This should get you in the ballpark but I wouldn't rely on this
for detailed modeling of say the tempco in the breakdown region.

-dan