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help: TSMC BJT spice model

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aindejeje

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Hello.
This is my first time doing mixed-signal IC design.
Im designing a CDP on Tanner and simulate it on T-SPICE.
and got the following error:

Fatal T-SPICE : Missing model declaration for "NPN"

I guess i need a BJT model for it.
SPICE model for TSMC (prefer 0.25um technology)
Can anyone help me?
 

aindejeje said:
I guess i need a BJT model for it.
SPICE model for TSMC (prefer 0.25um technology)
Pls. find here SPICE Model Parameters for several TSMC 0.25µ processes!
 

    aindejeje

    Points: 2
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erikl said:
aindejeje said:
I guess i need a BJT model for it.
SPICE model for TSMC (prefer 0.25um technology)
Pls. find here SPICE Model Parameters for several TSMC 0.25µ processes!

thanks for your help.
but whats are the:
MM NON EPI
LO MTL etc
 

aindejeje said:
... but whats are the:
MM NON EPI
LO MTL etc
These are all different 0.25µm processes (each process option has a unique name).
But meantime I discovered the files contain just S*PICE parameters for MOSfets, not for BJTs, sorry! :cry:
You should also specify, if you need a S*PICE model for a lateral or for a vertical npn. They can be quite different.
 

erikl said:
aindejeje said:
... but whats are the:
MM NON EPI
LO MTL etc
These are all different 0.25µm processes (each process option has a unique name).
But meantime I discovered the files contain just S*PICE parameters for MOSfets, not for BJTs, sorry! :cry:
You should also specify, if you need a S*PICE model for a lateral or for a vertical npn. They can be quite different.

yeah.no BJTs :cry:
 

Hi erikl,

I am Karthik.
I am trying to simulate a circuit having BJTs in spectre.
I need 0.35 micron tsmc BJT model because my need in BJT that operates at 5v. I am not sure whether it is lateral or vertical BJT i need.
 

karthikvenkatesh said:
Hi erikl,

I am Karthik.
I am trying to simulate a circuit having BJTs in spectre.
I need 0.35 micron tsmc BJT model because my need in BJT that operates at 5v.
Hi Karthik,
a 0.35 micron tsmc BJT model you can only get from TSMC if you sign an NDA, or through MOSIS, by a similar procedure.

You could perhaps get 'incognito' SPICE models for a similar 0.35 micron process, but the simulation results ain't necessarily identical. If you intend to produce a chip, it's a must to use the original models from the very process.

karthikvenkatesh said:
I am not sure whether it is lateral or vertical BJT i need.
Which model is available depends on the respective PDK. A 'standard' CMOS process usually includes a vertical pnp BJT (beta ≈ 2 .. 5), sometimes additionnally a lateral pnp (beta ≈ 20 .. 50). In any case their collectors are connected to the substrate. If you need uncommitted BJTs (also npn ones), you have to select a BICMOS process.
 

Erikl,
Thanks for your comments which is very helpful.
What I did is, I browsed through MOSIS site, got IBM 0.35 micron BJT NPN model whose forward beta is 100.
My specification is beta = 20. So i changed that forward beta and used those parameters in spectre for simulation.
This BJT model is for Bandgap reference design.
Some say, dont dwelve a lot into all of the BJT model parameters. Just take the beta=20. Since the role of BJT here in bandgap is not gain oriented but just to nullify the temperature coefficient.


Thanks and regards,
Karthik
 

karthikvenkatesh said:
... IBM 0.35 micron BJT NPN model whose forward beta is 100.
Probably from a BICMOS process.

karthikvenkatesh said:
My specification is beta = 20. So i changed that forward beta and used those parameters in spectre for simulation.
This BJT model is for Bandgap reference design.
Some say, dont dwelve a lot into all of the BJT model parameters. Just take the beta=20. Since the role of BJT here in bandgap is not gain oriented but just to nullify the temperature coefficient.
That's ok. Even simple diodes would work. BJTs beta > 1 achieve better accuracy, however.
Rgds, erikl.
 

Hello,

Can you please send me the link to the BJT NPN model . Thanks in advance.

Regards.


Erikl,
Thanks for your comments which is very helpful.
What I did is, I browsed through MOSIS site, got IBM 0.35 micron BJT NPN model whose forward beta is 100.
My specification is beta = 20. So i changed that forward beta and used those parameters in spectre for simulation.
This BJT model is for Bandgap reference design.
Some say, dont dwelve a lot into all of the BJT model parameters. Just take the beta=20. Since the role of BJT here in bandgap is not gain oriented but just to nullify the temperature coefficient.


Thanks and regards,
Karthik
 

open your tsmc technology file
probably u ll be having there pmos nmos parameters

now add this line there
.model PNPDIODE D IS=1e-18 n=1
and in interconnections use the above name PNPDIODE for refernce



lets see the image & work out example here sayeesh.png








now for this we are having fully defined cmos models but no BJT as 3 are used here D1,2,3
so if you are not using this circuit for layout etc then just u can add this line & it will serve your purpose of BJT
i am posting full t-spice for this circuit,
****************************************************************
.option scale=1u post
.dc VDD 0 6 1m temp 0 100 25

VDD VDD 0 DC 5
Vop Vop 0 DC 0
Von VDD Von DC 0
Vmeas1 Vmeas1 0 DC 0
Vmeas2 Vmeas2 0 DC 0

M1B Vbiasn Vbiasn Vd1 0 N_1u L=2 W=10
M2B n2 Vbiasn Vr 0 N_1u L=2 W=10
M1T vncas vncas vbiasn 0 N_1u L=2 W=10
M2T vpcas vncas n2 0 N_1u L=2 W=10
M3T n1 Vbiasp VDD VDD P_1u L=2 W=30
M4T Vbiasp Vbiasp VDD VDD P_1u L=2 W=30
M3B vncas Vpcas n1 VDD P_1u L=2 W=30
M4B Vpcas Vpcas Vbiasp VDD P_1u L=2 W=30

M5T n3 vbiasp VDD VDD P_1u L=2 W=30
M5B Vref vpcas n3 VDD P_1u L=2 W=30
RL Vref vd3 489k TC1=0.002

Rb Vr vd2 52k TC1=0.002

D1 Vd1 0 PNPDIODE
D2 vd2 0 PNPDIODE 8
D3 vd3 0 PNPDIODE 8
.model PNPDIODE D IS=1e-18 n=1

** Start-up Circuit
MSU1 Vsur Vbiasp VDD VDD P_1u L=2 W=30
MSU2 Vncas Vsur Vpcas VDD P_1u L=2 W=30
MSU3 Vsur Vsur ns1 0 N_1u L=10 W=10
MSU4 ns1 ns1 ns2 0 N_1u L=10 W=10
MSU5 ns2 ns2 0 0 N_1u L=10 W=10

.include tsmccmos_models.txt

.end
**********************************************

Hope it ll be helpfull :) :roll:
 

open your tsmc technology file
probably u ll be having there pmos nmos parameters

now add this line there
.model PNPDIODE D IS=1e-18 n=1
and in interconnections use the above name PNPDIODE for refernce



lets see the image & work out example here View attachment 70821








now for this we are having fully defined cmos models but no BJT as 3 are used here D1,2,3
so if you are not using this circuit for layout etc then just u can add this line & it will serve your purpose of BJT
i am posting full t-spice for this circuit,
****************************************************************
.option scale=1u post
.dc VDD 0 6 1m temp 0 100 25

VDD VDD 0 DC 5
Vop Vop 0 DC 0
Von VDD Von DC 0
Vmeas1 Vmeas1 0 DC 0
Vmeas2 Vmeas2 0 DC 0

M1B Vbiasn Vbiasn Vd1 0 N_1u L=2 W=10
M2B n2 Vbiasn Vr 0 N_1u L=2 W=10
M1T vncas vncas vbiasn 0 N_1u L=2 W=10
M2T vpcas vncas n2 0 N_1u L=2 W=10
M3T n1 Vbiasp VDD VDD P_1u L=2 W=30
M4T Vbiasp Vbiasp VDD VDD P_1u L=2 W=30
M3B vncas Vpcas n1 VDD P_1u L=2 W=30
M4B Vpcas Vpcas Vbiasp VDD P_1u L=2 W=30

M5T n3 vbiasp VDD VDD P_1u L=2 W=30
M5B Vref vpcas n3 VDD P_1u L=2 W=30
RL Vref vd3 489k TC1=0.002

Rb Vr vd2 52k TC1=0.002

D1 Vd1 0 PNPDIODE
D2 vd2 0 PNPDIODE 8
D3 vd3 0 PNPDIODE 8
.model PNPDIODE D IS=1e-18 n=1

** Start-up Circuit
MSU1 Vsur Vbiasp VDD VDD P_1u L=2 W=30
MSU2 Vncas Vsur Vpcas VDD P_1u L=2 W=30
MSU3 Vsur Vsur ns1 0 N_1u L=10 W=10
MSU4 ns1 ns1 ns2 0 N_1u L=10 W=10
MSU5 ns2 ns2 0 0 N_1u L=10 W=10

.include tsmccmos_models.txt

.end
**********************************************

Hope it ll be helpfull :) :roll:

---------- Post added at 16:50 ---------- Previous post was at 16:35 ----------

.model PNPDIODE D IS=1e-18 n=1
i have defined here in which n=1 just defines level of bjt model i.e. =1 so only is that is breaking point of bjt i am mentioning here which you can vary,.
also try to not be completly dependent on model technology files of companies, like sumtimes u want to implement your design <<innovatively>> or tech file are not having that parameter value,, so always just put .model command , edit , set level, make ,edit or add parameters accordingly ..
the above mentioned tsmc models is for 1micron tsmc technolgy for that BJT with IS=1e-18 i have used ,, but for 0.25u which u are using definitly value will be different , which is headache :) beacuse when i added resitor RL Vref vd3 489k TC1=0.002 TC temp coefficient was very hard to find ,, so process goes like that ,,
also switching to bicmos is very helpfull :)
 

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