Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronic 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.

Register Log in

question on the power network in floorplan

Status
Not open for further replies.

jackson_peng

Full Member level 2
Joined
Apr 11, 2005
Messages
141
Helped
23
Reputation
46
Reaction score
9
Trophy points
1,298
Location
Shanghai, China
Activity points
2,380
when draw the power supply network in floorplan,
why should we use the top two metal?
can anyone give the reason.
 

jliang

Newbie level 4
Joined
Feb 4, 2005
Messages
5
Helped
1
Reputation
2
Reaction score
0
Trophy points
1,281
Activity points
50
jackson_peng said:
when draw the power supply network in floorplan,
why should we use the top two metal?
can anyone give the reason.
Less resistance? In cmos process, top metal layers have less sheet resistance. Correct me if I am wrong.
 

anjali

Full Member level 3
Joined
Aug 16, 2005
Messages
173
Helped
14
Reputation
28
Reaction score
6
Trophy points
1,298
Activity points
3,033
there should not be any volage swing for the cells/macros, if so they may go to metastable state or transistion delay problems etc.

so power network should have very less resistance. so we prefer the top 2 metals for power routing.
 

nmtr

Member level 2
Joined
May 16, 2001
Messages
46
Helped
2
Reputation
4
Reaction score
2
Trophy points
1,288
Location
a Chinese university
Activity points
580
jackson_peng said:
when draw the power supply network in floorplan,
why should we use the top two metal?
can anyone give the reason.
really??? In our lab the top metal is used to route gobal and critical net and only the second and third level from top is used to power. any comments???
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top