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shaq
Joined: 23 Jul 2005
Posts: 321
Helped: 9
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 16 Nov 2005 4:19 How to calculate the width of VDD & GND ? |
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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?
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huojinsi
Joined: 21 Jan 2005
Posts: 260
Helped: 17
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| 16 Nov 2005 5:59 Re: How to calculate the width of VDD & GND ? |
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| 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.
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sunking
Joined: 25 May 2004
Posts: 914
Helped: 46
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| 16 Nov 2005 8:29 How to calculate the width of VDD & GND ? |
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| you should consider to the IR voltage, too
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Syukri
Joined: 09 Aug 2005
Posts: 254
Helped: 13
Location: Malaysia
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| 16 Nov 2005 9:32 Re: How to calculate the width of VDD & GND ? |
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| Do you guys means the width of Vdd is the with of metal1, if so why can we just follow the lambda rules?
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flushrat
Joined: 25 Jan 2005
Posts: 191
Helped: 15
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| 16 Nov 2005 10:58 Re: How to calculate the width of VDD & GND ? |
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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.
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shaq
Joined: 23 Jul 2005
Posts: 321
Helped: 9
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| 16 Nov 2005 11:28 Re: How to calculate the width of VDD & GND ? |
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| Syukri wrote: |
| 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...
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