Zener Diode model Cadence virtuoso

[kenambo]

Hi all

I want to implement a Zener diode using analogLib diode instance

How to model a Zener diode like 1N5221 ?

means i want to model a real zener diode into cadence?

how to get the required parameters and values?

thanks

 

[erikl]

The extractor should be able to extract it as a Zener diode. If not, you could at least use the extracted junction capacitance cj.
Here is an example spice model from an early 0.18µm process:

*************************************************************
** 0.18µm ** ZENER DIODE ** Bvd 16-Jul-2001 **
*************************************************************

.subckt zener 1 2
d1 1 2 zener_diod1
d2 2 1 zener_diod2
d3 0 2 zener_clamp
.ends zener
*
.model zener_diod1 d
+ bv = 5.6425
+ cj = 9.353E-14
+ level=1
+ is=1e-20 n=0.2118 ibv=1e-3
+ rs=91.5316 tcv=-1.600e-03 eg=0.1 xti=0
+ mj=0.3552 pb=0.8144
*
.model zener_diod2 d
+ level=1
+ is=4.717e-13 n=20.5734 bv=20 ibv=1e-3
+ rs=10 eg=0.2975 xti=227.3035
*
.model zener_clamp d
+ level=1
+ is=1e-22 n=1 bv=17.5 ibv=1e-3
+ rs=10 tcv=-1e-03 eg=0 xti=0
*

Adjust the zener breakdown voltage bv of diod1 @ breakdown current ibv .

 

[dick_freebird]

I've only ever used the diode (standard) model for zener fitting
and had no issues. You just use the analogLib symbol, give it
the model name, make sure you have a .inc file that properly
declares the model, and make sure that include-file is picked
up (model libraries list). If you mean to keep on using the
model, it might be easier to append its text inside an already-
auto-hooked-up file (like the butt end of a PDK include.inc
or whatever, if there is a consistent head or tail to the chain
that you can edit).

Probably can find a reasonably fitted model from one of the
vendors' support pages, or a PSPICE or LTSPICE lib from
the internet. A little syntax buffing and good to go.