Stats

Locked Locked
Replies 7
Subscribers 126
Views 18287
Members are here 0

This discussion has been locked.

You can no longer post new replies to this discussion. If you have a question you can start a new discussion

Transistors in series

Hi! First of all, sorry if I'm posting it in the wrong place. Moderator please move it to the right place.

My question is: when I change the multiplicity or the number of finger in a FET transistor, it means I'm putting them in parallel.

My question is how I put them in series, without doing it manually.

Thanks.

Parents

Andrew Beckett over 11 years ago

Hi Damien,
Are you sure you labelled the nets correctly? I don't see a need to put a wire between the two. I just drew the attached picture, and got this (spectre netlist):
// Library name: opamp090
// Cell name: itertran
// View name: schematic
M1\<19\> (D G VDNext\<18\> B) gpdk090_nmos1v w=(120n) l=100n as=69.6f \
        ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<18\> (VDNext\<18\> G VDNext\<17\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<17\> (VDNext\<17\> G VDNext\<16\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<16\> (VDNext\<16\> G VDNext\<15\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<15\> (VDNext\<15\> G VDNext\<14\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<14\> (VDNext\<14\> G VDNext\<13\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<13\> (VDNext\<13\> G VDNext\<12\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<12\> (VDNext\<12\> G VDNext\<11\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<11\> (VDNext\<11\> G VDNext\<10\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<10\> (VDNext\<10\> G VDNext\<9\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<9\> (VDNext\<9\> G VDNext\<8\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<8\> (VDNext\<8\> G VDNext\<7\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<7\> (VDNext\<7\> G VDNext\<6\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<6\> (VDNext\<6\> G VDNext\<5\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<5\> (VDNext\<5\> G VDNext\<4\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<4\> (VDNext\<4\> G VDNext\<3\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<3\> (VDNext\<3\> G VDNext\<2\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<2\> (VDNext\<2\> G VDNext\<1\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<1\> (VDNext\<1\> G VDNext\<0\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<0\> (VDNext\<0\> G S B) gpdk090_nmos1v w=(120n) l=100n as=69.6f \
        ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
As you can see, that's correct and not how you describe. I can't see how a PDK could cause this to mess up - it would be pretty hard to make it misbehave!
Regards,
Andrew.
- damien.png
- View
- Hide
Cancel
Vote Up 0 Vote Down

Cancel

Reply

Andrew Beckett over 11 years ago

Hi Damien,
Are you sure you labelled the nets correctly? I don't see a need to put a wire between the two. I just drew the attached picture, and got this (spectre netlist):
// Library name: opamp090
// Cell name: itertran
// View name: schematic
M1\<19\> (D G VDNext\<18\> B) gpdk090_nmos1v w=(120n) l=100n as=69.6f \
        ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<18\> (VDNext\<18\> G VDNext\<17\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<17\> (VDNext\<17\> G VDNext\<16\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<16\> (VDNext\<16\> G VDNext\<15\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<15\> (VDNext\<15\> G VDNext\<14\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<14\> (VDNext\<14\> G VDNext\<13\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<13\> (VDNext\<13\> G VDNext\<12\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<12\> (VDNext\<12\> G VDNext\<11\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<11\> (VDNext\<11\> G VDNext\<10\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<10\> (VDNext\<10\> G VDNext\<9\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<9\> (VDNext\<9\> G VDNext\<8\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<8\> (VDNext\<8\> G VDNext\<7\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<7\> (VDNext\<7\> G VDNext\<6\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<6\> (VDNext\<6\> G VDNext\<5\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<5\> (VDNext\<5\> G VDNext\<4\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<4\> (VDNext\<4\> G VDNext\<3\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<3\> (VDNext\<3\> G VDNext\<2\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<2\> (VDNext\<2\> G VDNext\<1\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<1\> (VDNext\<1\> G VDNext\<0\> B) gpdk090_nmos1v w=(120n) l=100n \
        as=69.6f ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
M1\<0\> (VDNext\<0\> G S B) gpdk090_nmos1v w=(120n) l=100n as=69.6f \
        ad=69.6f ps=1.04u pd=1.04u m=(1)*(1)
As you can see, that's correct and not how you describe. I can't see how a PDK could cause this to mess up - it would be pretty hard to make it misbehave!
Regards,
Andrew.
- damien.png
- View
- Hide
Cancel
Vote Up 0 Vote Down

Cancel

Children

No Data

Community Guidelines

The Cadence Design Communities support Cadence users and technologists interacting to exchange ideas, news, technical information, and best practices to solve problems and get the most from Cadence technology. The community is open to everyone, and to provide the most value, we require participants to follow our Community Guidelines that facilitate a quality exchange of ideas and information. By accessing, contributing, using or downloading any materials from the site, you agree to be bound by the full Community Guidelines.