Cadence Mixed-Signal Circuit Design Environment User Guide
Interface Element Macro Models
October 2003
80
Product Version 5.0
inline subckt CML3_d2a (anode gnd)
...
ends CML3_d2a
6. Add the parameter declaration. Be sure to add the parameter
src
to D2A models. You
can also specify default values for each parameter.
7. Rename the IE primitive with the name of the IE model, such as CML3_d2a. This
indicates that the IE primitive is the inline component.
8. Replace the
"&1"
parameter, which represents the digital source, with
src
. Remove the
quotation marks ("") from the
src
parameter value of the IE primitive.
9. Replace the
&1
(unquoted) parameter, which represents the digital node, with
dnode
.
10. Replace the
&2
parameter, which represents the interface net, with the string
anode
.
11. Replace node 0 with
gnd
.
12. Replace parameters
&3
and higher with the corresponding Spectre parameter names.
13. (Optional) Make cosmetic changes to improve readability. You can make cosmetic
changes after you have tested the model.
The
CML3_d2a.S
model file for SpectreS simulation looks like this:
da&1 &1 0 d2a src="&1" val0=&3 val1=&4 rise=&5 fall=&6
X&1 &1 &2 C&1
.SUBCKT C&1 1 70
VSS 10 0 -5
R1 10 20 750
Q1 40 30 20 0 TN1
VCS 30 0 -3.8
Q2 0 50 40 0 TN1
Q3 70 60 40 0 TN1
VBB1 50 0 -0.2
R2 70 0 750
VBB2 80 0 -0.4
E1 80 60 1 0 1
.MODEL TN1 NPN is=1.5e-16 bf=250 nf=1 vaf=150 ikf=7e-4 &
ne=1.5 br=2 nr=1 var=5 ikr=3e-3 isc=0 nc=1.5 rb=600 re=3 &
rc=75 cje=40e-15 vje=0.91 mje=0.35 tf=20e-12 ptf=10 cjc=40e-15 &
vjc=0.72 mjc=0.45 xcjc=0.25 tr=20e-11 cjs=75e-15 vjs=0.62 &
mjs=0.47 xtb=1.5 eg=1.12 xti=3.5 fc=0.5
.ENDS C&1
After conversion, the model file for Spectre simulation looks like this: