Continue to Site

# A question of metal path width

Status
Not open for further replies.

#### limkon

##### Newbie level 4
Hey all!
In layout, should the width of a power(12V) metal path be wider, or narrower?
(e.x. if a 2um width metal path(from PAD to block) is acceptable in a 0.18um process)
THX!

limkon said:
Hey all!
In layout, should the width of a power(12V) metal path be wider, or narrower?
(e.x. if a 2um width metal path(from PAD to block) is acceptable in a 0.18um process)
THX!

The current density of metal line(M1-M5) is about 1mA/um. You can choose the metal width of power line according to the principle. Usually, the power line shoud be as wide as possible to reduce the voltage drop.

limkon said:
Hey all!
In layout, should the width of a power(12V) metal path be wider, or narrower?
(e.x. if a 2um width metal path(from PAD to block) is acceptable in a 0.18um process)
THX!

This will depend in the current that is flowing in your Power lines.

You can compute for the allowed Metal width if you know how much current is needed for the Power line.

Look at the PDK about the current density of different metals.And ask your designer how much current is flowing in the Power line.

Imax(Mx) = DxW

where Imax - maximum allowed current
D - current density of metal
W - Width of metal

therefore you can compute for the W

W = Imax/D

Cheers

Hi

You should take care about IR drop

regards

analayout

It depends on how much current flow through the metal. Generally 1um width metal can flow 1uA current.

Status
Not open for further replies.