What does MF & OS mean?

[penghan]

I found this in a Spice Netlist

"XMN0 OUT1 IN 0 0 NCH W=60U L=0.24U MF=10 OS=8 "

MF may be means Transistor's Multi-fingers,but what is OS?

 

[Hughes]

The first letter is 'X'. This implies XMN0 is a subckt call statement calling a subckt named NCH. Search the netlist to find
.subckt NCH ...
You can find what MF and OS means.

 

[penghan]

It is not a subckt,but a transistor.
There is no definition of XMN0 in that netlist.The lib is TSMC 0.25.
Then how to understand it?

 

[lokeyh]

It is probably loaded elsewhere by the spice files. Check for the files loaded to run with the netlist as well. X is for sub-circuit and M is for MOSFET.

 

[Hughes]

It is not a subckt,but a transistor.
There is no definition of XMN0 in that netlist.The lib is TSMC 0.25.
Then how to understand it?

It is not the definition for XMN0, but that of NCH. It may be defined in the include file or lib file. Check the TSMC's model files.

Using subckt rather than transistor model can include more parasitics.

 

[penghan]

The only included file in this netlist is TSMC025.lib,no others.
We usually name MOSFET as M**,but this netlist with XM** running successfully in simulation.

I didn't find any XM** definition in the PDK of TSMC 0.25.
It is strange.

 

[Hughes]

Do not find XM definition. Find the NCH definition.
Search the file 'TSMC025.lib'. It should have a line begin with:
.subckt NCH
or
.macro NCH

Ignore the case when searching.

 

[penghan]

Do not find XM definition. Find the NCH definition.
Search the file 'TSMC025.lib'. It should have a line begin with:
.subckt NCH
or
.macro NCH

Ignore the case when searching.

Yes,u r right.i find NCH in the lib.
Why he/she use XM** but not M*?
Because he/she can use MF & OS only with XM**?
If so,what does OS mean?There is no explanation about OS in the lib.

 

[Hughes]

Using XM rather M is to include some parasitic devices into the mosfet model.

Since MF and OS are not standard MOSFET model parameters, I recomended you to post here the NCH subckt definition in order to find what MF and OS mean exactly.

Just post the section from
.subckt NCH
or
.macro NCH
to
.ends