McSim
Newbie level 4
Hi all!
I have a problem with Verilog-A modeling in Spectre 6.x.
I use BSIM3 model implemented in Verilog-A by Geoffrey Coram (the file was available at Silvaco and then - at Simucad site some time ago). See attached file. I have successfully used it with Spectre 5.1.41.
My "standard" task is to simulate MOSFET DC characteristics. Transistor is taken from PDK. In model file there is a subckt which uses the instance described as Verilog-A module (using "ahdl_include"). All SPICE parameters are described as instance parameters (instance inside subcircuit):
, where "bsim3mos" is verilog-A module.
But when I try to simulate this with Spectre 6.0 or even with Spectre 6.2 some Verilog-A module parameters are not recognized as instance parameters by simulator (and some parameters, e.g. W, L, TYPE and TOX are still recognized, but U0 isn't). Warning message is generated:
"U0 is not a valid parameter for an instance bsim3mos. Ignored"
And then characteristics with default values (defined in Verilog-A module) of parameters are simulated.
Could you help me to solve this problem or just give an advice how should I search the possible reasons?
P.S. By the way, does anybody know why the files with Verilog-A MOSFET models are not available now?
I have a problem with Verilog-A modeling in Spectre 6.x.
I use BSIM3 model implemented in Verilog-A by Geoffrey Coram (the file was available at Silvaco and then - at Simucad site some time ago). See attached file. I have successfully used it with Spectre 5.1.41.
My "standard" task is to simulate MOSFET DC characteristics. Transistor is taken from PDK. In model file there is a subckt which uses the instance described as Verilog-A module (using "ahdl_include"). All SPICE parameters are described as instance parameters (instance inside subcircuit):
Code:
inline subckt nmos_tn (d g s b)
parameters w=1E-7 l=1E-7 PAR=1 as=0 ad=0 ps=0 pd=0 nrd=0 nrs=0
...
nmos_tn (d g s b) bsim3mos W=w L=l AD=ad AS=as PD=pd PS=ps ...
+ TYPE=1
...
+ U0=0.035597185
...
ends nmos_tn
, where "bsim3mos" is verilog-A module.
But when I try to simulate this with Spectre 6.0 or even with Spectre 6.2 some Verilog-A module parameters are not recognized as instance parameters by simulator (and some parameters, e.g. W, L, TYPE and TOX are still recognized, but U0 isn't). Warning message is generated:
"U0 is not a valid parameter for an instance bsim3mos. Ignored"
And then characteristics with default values (defined in Verilog-A module) of parameters are simulated.
Could you help me to solve this problem or just give an advice how should I search the possible reasons?
P.S. By the way, does anybody know why the files with Verilog-A MOSFET models are not available now?