How to get early voltage from hspice simulation

[arafatsagar]

calculating early voltage from pvag

I need to know the early voltage from hspice parameters or from hspice *.lis file. Is it possible to get the early voltage from hspice simulation?

 

[FvM]

In simulation, you get exactly the early voltage parameter, that is set in the respective transistor model. The usual SPICE parameter name is VAF. Consult a HSPICE reference manual for details. See a semiconductor textbook how to extract the early voltage from transistor characteristics.

 

[arafatsagar]

my code is-

MOSFET I-V characteristics
.options node nopage
.op
vds nd 0
vgs ng 0
M1 nd ng 0 0 cmosn L=.18u W=18u
.dc vds 0 15 .001 vgs 0 5 .5
.print V(ng) I(M1)
.include 'tsmc018.lib'
.end

but i am getting VAF nowhere. the 'tsmc018.lib' doesnt include the VAF. the listing file *.lis has no parameter like VAF.
please help me out. i need to know how can i get the early voltage,

 

[FvM]

Early voltage is a BJT parameter. MOSFET has LAMBDA channel length modulation parameter in level 1 and 2 instead. (LAMBDA = 1/VAF).Don't know about the level involved with your library.

Generally, the MOSFET output resistance shows a more complex dependency of operating point, that can't be expressed with a single VAF respectively LAMBDA parameter.

 

[arafatsagar]

i am using level 49 but getting no LAMBDA or VAF.


.MODEL CMOSN NMOS ( LEVEL = 49

+VERSION = 3.1 TNOM = 27 TOX = 4.1E-9

+XJ = 1E-7 NCH = 2.3549E17 VTH0 = 0.3662473

+K1 = 0.5864999 K2 = 1.127266E-3 K3 = 1E-3

+K3B = 0.0294061 W0 = 1E-7 NLX = 1.630684E-7

+DVT0W = 0 DVT1W = 0 DVT2W = 0

+DVT0 = 1.2064649 DVT1 = 0.4215486 DVT2 = 0.0197749

+U0 = 273.8094484 UA = -1.40499E-9 UB = 2.408323E-18

+UC = 6.504826E-11 VSAT = 1.355009E5 A0 = 2

+AGS = 0.4449958 B0 = 1.901075E-7 B1 = 4.99995E-6

+KETA = -0.0164863 A1 = 3.868769E-4 A2 = 0.4640272

+RDSW = 123.3376355 PRWG = 0.5 PRWB = -0.197728

+WR = 1 WINT = 0 LINT = 1.690044E-8

+XL = 0 XW = -1E-8 DWG = -4.728719E-9

+DWB = -2.452411E-9 VOFF = -0.0948017 NFACTOR = 2.1860065

+CIT = 0 CDSC = 2.4E-4 CDSCD = 0

+CDSCB = 0 ETA0 = 2.230928E-3 ETAB = 6.028975E-5

+DSUB = 0.0145467 PCLM = 1.3822069 PDIBLC1 = 0.1762787

+PDIBLC2 = 1.66653E-3 PDIBLCB = -0.1 DROUT = 0.7694691

+PSCBE1 = 8.91287E9 PSCBE2 = 7.349607E-9 PVAG = 1.685917E-3

+DELTA = 0.01 RSH = 6.7 MOBMOD = 1

+PRT = 0 UTE = -1.5 KT1 = -0.11

+KT1L = 0 KT2 = 0.022 UA1 = 4.31E-9

+UB1 = -7.61E-18 UC1 = -5.6E-11 AT = 3.3E4

+WL = 0 WLN = 1 WW = 0

+WWN = 1 WWL = 0 LL = 0

+LLN = 1 LW = 0 LWN = 1

+LWL = 0 CAPMOD = 2 XPART = 0.5

+CGDO = 8.23E-10 CGSO = 8.23E-10 CGBO = 1E-12

+CJ = 9.466429E-4 PB = 0.8 MJ = 0.3820266

+CJSW = 2.608154E-10 PBSW = 0.8 MJSW = 0.102322

+CJSWG = 3.3E-10 PBSWG = 0.8 MJSWG = 0.102322

+CF = 0 PVTH0 = -2.199373E-3 PRDSW = -0.9368961

+PK2 = 1.593254E-3 WKETA = -2.880976E-3 LKETA = 7.165078E-3

+PU0 = 6.777519 PUA = 5.505418E-12 PUB = 8.84133E-25

+PVSAT = 2.006286E3 PETA0 = 1.003159E-4 PKETA = -6.759277E-3

+NOIMOD=2.0E+00 NOIA=1.3182567385564E+19

+NOIB=144543.977074592 NOIC=-1.24515784572817E-12 EF=0.92 EM=41000000 )

here is the list of all my parameters available in 'tsmc018.lib'. i need the early voltage. please help me to calculate it if there is no parameter available.

 

[FvM]

See a semiconductor textbook how to extract the early voltage from transistor characteristics.