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Issues on translating device model file

Question asked by TNAKA on Jun 2, 2003
Latest reply on Jun 8, 2003 by TNAKA
When I translated Spectre's model files into ADS syntax using
"nettrans(Netlist Translator (*) 230.300 Apr  6 2003)",
I noticed some defects in translation.
My setting for option of "nettrans" is "-pl spectre -g -n -pp".


(1) "bvsub" has been mistakenly mapped to "wBvwub" in BJT model
For example, see following results, here first is Spectre model and second is
translated ADS format.

model NPNlower bjt type=npn is=73.6e-18 bf=121 nf=1 vaf=35 ikf=96e-3 \
[snipped]
  bvbe=3 bvbc=14 bvsub=14 kf=0.55e-10 af=1.8 iss=1e-16

model NPNlower BJT wVbcfwd=0.2 Imax=1000 Tnom=27 wVsubfwd=0.2 NPN=yes
Is=73.6e-18 Bf=121 \
[snipped]
     Tre1=0 Tre2=0 wBvbe=3 wBvbc=14 wBvwub=14 Kf=0.55e-10 Af=1.8
Iss=1e-16 PNP=no

Maybe this is simple typo in program "nettrans".


(2) "Width" and "Length" should be changed to "W" and "L" in Level-3 MOSFET
model
"nettrans" adds default Width and Length for device.
But parameter name such as "Width" and "Length" is not valid parameter for
MOSFET
in ADS. So "Width" and "Length" must be changed to "W" and "L".
For example, see following results, here first is Spectre model and second is
translated ADS format.

model nmos301 mos3  type=n   \
vto=0.725  uo=585.0  tox=23.5n  nsub=3.27e+16 \
nfs=3.5e+11  vmax=1.6e+05  eta=0.012  kappa=0.13  theta=0.080 \
delta=2.62  xj=0.08u    rsh=533.0 \
ld=0.250u  cgdo=2.1e-10  cgso=2.1e-10  af=1.0  kf=2.5e-28 \
cj=4.4e-04  mj=0.370  cjsw=3.4e-10  mjsw=0.220  pb=1.100

model nmos301 MOSFET Width=3e-6 Imax=1 Pbsw=0.8 Tnom=27 Idsmod=3
Eg=1.12452 Vmax=1.6e+05 \
     Kp=2.0718e-5 Phi=0.7 Length=3e-6 Nsub=3.27e+16 NMOS=yes Vto=0.725
Uo=585.0 Tox=23.5n \
     Nfs=3.5e+11 Eta=0.012 Kappa=0.13 Theta=0.080 Delta=2.62 Xj=0.08u
Rsh=533.0 Ld=0.250u \
     Cgdo=2.1e-10 Cgso=2.1e-10 Af=1.0 Kf=2.5e-28 Cj=4.4e-04 Mj=0.370
Cjsw=3.4e-10 Mjsw=0.220 \
     Pb=1.100 PMOS=no

Here Width=3e-6 and Length=3e-6 are invalid parameters.
I have to delete them or change them to W=3e-6 and L=3e-6.

(3) nqsmod parameter in Spectre's bsim3v3 model.
"nettrans" prints following warning.
  WARNING: The following parameter from element nch_1 is not supported by ADS
  and will be ignored in translation:
       nqsmod=0

But I don't think this message is appropriate.
I think following message is appropriate.

  "nqsmod" is supported as instance parameter "Nqsmod" in MOSFET.  

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