Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

What define Cgb Cdb in hspice simulation? Help!

Status
Not open for further replies.

xiexi

Member level 4
Joined
Jan 14, 2005
Messages
79
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,286
Activity points
613
The Cgb and Cdb is defined by layout diffusion size which is AD, PD, AS, PS. But I am confused that when I simulate using level 49 model the Cgb and Cdb exist without writing AD, PD, AS, PS parameter. I wonder how to defind these parameters in hspice program if I don't write them. Thanks!
 

castrader

Member level 1
Joined
Jun 8, 2005
Messages
36
Helped
7
Reputation
14
Reaction score
1
Trophy points
1,288
Activity points
1,468
i think cgd cdb cgs is include in the models not in the spice file.
you can use lx18 - lx34 see it (details in hspice mannual)
 

    xiexi

    Points: 2
    Helpful Answer Positive Rating

farrokhiyan

Junior Member level 3
Joined
Sep 17, 2007
Messages
29
Helped
3
Reputation
6
Reaction score
1
Trophy points
1,283
Activity points
1,473
Hi dear friend
You can specify device characteristics for default values. you can see more information in hspice manual. the default values are determined in technology file.

See this picture :



Regards
 

    xiexi

    Points: 2
    Helpful Answer Positive Rating

pfd001

Advanced Member level 1
Joined
Jul 23, 2005
Messages
410
Helped
45
Reputation
90
Reaction score
10
Trophy points
1,298
Activity points
3,214
xiexi said:
The Cgb and Cdb is defined by layout diffusion size which is AD, PD, AS, PS. But I am confused that when I simulate using level 49 model the Cgb and Cdb exist without writing AD, PD, AS, PS parameter. I wonder how to defind these parameters in hspice program if I don't write them. Thanks!

If you dont define AD,PD,AS,PS, spice will use the default settting. They can be calculated by the W, L
 

    xiexi

    Points: 2
    Helpful Answer Positive Rating
Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top