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.

[SOLVED] [Moved]: Impact of multiplicity on RF transistors?

Status
Not open for further replies.

Fávero Santos

Junior Member level 1
Joined
Jul 9, 2013
Messages
15
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,432
Hello, all. Hope everyone's doing fine.

I'm synthesizing a microwave PA @ 2.4 GHz using sub 200nm CMOS technology. I've choosen cascode topology. The upper transistor configs are: wtot = 400u/multiplicity, number of fingers = 3 and multiplicity = 9.

My doubt: Is there any constraint when using a large multiplicity number as I've used? How the large multiplicity number will affect my layout?

Thank you all

Fávero
 

erikl

Super Moderator
Staff member
Joined
Sep 9, 2008
Messages
8,106
Helped
2,694
Reputation
5,368
Reaction score
2,297
Trophy points
1,393
Location
Germany
Activity points
44,076
Is there any constraint when using a large multiplicity number as I've used? How the large multiplicity number will affect my layout?

m=9 isn't too large, if you keep the 9 equal units closely together, e.g. in a 3x3 array.
 

AMS012

Full Member level 4
Joined
Oct 29, 2012
Messages
232
Helped
48
Reputation
98
Reaction score
59
Trophy points
1,308
Location
India
Activity points
2,759
More the multiplier, more the parasitic due to layout (more routing connecting different multiplier). But if you are using RF transistor model for the design, I assume the parasitic are well modeled and you will see very little change from schematic to layout results. However, there is a limit on the maximum number of fingers that can be used. Multiplier of 9 is not too large.
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top