john7796
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Hi,
On metal line has 700um long, 0.25um width,
for 0.2fF/1um, the capacitance of the metal line is 0.2*700=140fF.
If the metal line need run up to 1GHz.
The peak current is V/R, R=t/5C=1ns/5*140fF=1.4k.
I=V/R=1.8/1.4K=1.28mA.
But the metal width is 0.25um=> only can run 250uA.
So the metal line width needs up to 1.28um to run 1.28mA.
However, the metal line capacitance is larger for lager width.
So the peak current needs more larger, this becomes to infinite loop.
Please help to solve this question. Thanks a lot.
John
On metal line has 700um long, 0.25um width,
for 0.2fF/1um, the capacitance of the metal line is 0.2*700=140fF.
If the metal line need run up to 1GHz.
The peak current is V/R, R=t/5C=1ns/5*140fF=1.4k.
I=V/R=1.8/1.4K=1.28mA.
But the metal width is 0.25um=> only can run 250uA.
So the metal line width needs up to 1.28um to run 1.28mA.
However, the metal line capacitance is larger for lager width.
So the peak current needs more larger, this becomes to infinite loop.
Please help to solve this question. Thanks a lot.
John