How to calculate the width of VDD & GND ?

[shaq]

Dear all,

I'll make a layout of OP Amp after a few days.

Now, I have a little problem, that is ,how to calculate the width of metal1 of VDD & GND?

 

[huojinsi]

First,u must know the current value I of passing the metal of VDD&GND.Then according to the formula W*H=I/Id (W represents the width of metal,H represents the thickness of metal,Id represents the density of metal), u can get the width of metal beause the value of H and Id is offered by foundry.

 

[sunking]

you should consider to the IR voltage, too

 

[Syukri]

Do you guys means the width of Vdd is the with of metal1, if so why can we just follow the lambda rules?

 

[flushrat]

The IR drop,especially of power bus, is very important for whole chip.
The minmum width of power should be calculated according to the maxmum R permitted.

 

[shaq]

Do you guys means the width of Vdd is the with of metal1, if so why can we just follow the lambda rules?

Dear Syukri,

I use Virtuoso layout editor,so how can I setup something to follow the lambda rules ?

Thanks so much...