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I think in this case you would be better off with LDO-like structure. So make nice flat bgap and feed it as reference to ldo - this way you will have flat voltage over temp. You can generate 2.5V directly if you dump current reference to resistors - but I would think you will have a bit problem...
a) what is your substrate (wafer) P or N. If P then your NMOS is probably not in separate NWELL and so guardring will not help.
b) draw a crossection and look for all the diodes in the structure - that will show you that guardring is not good.
c) best solution would be to keep all digital or...
If you have power ics then you should look at their recommended layout. The issue is that if you use one larcge GND plane the voltage from the regulator might not be correct. Usually the IC behind the regulator must be connected to regulator's output AND gnd. Then you voltage is best specified...
Your simulation is in my opinion best defined in old logic - HC or FACT. This appnote will show you the typical simulation /test circuit and tpzl/tphz definition.
https://www.onsemi.com/pub/Collateral/AND8277-D.PDF
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Your simulation is in my opinion best defined in old...
smaller gate length is decided long time ago by Mr. Moore and everybody tries to follow.
Every single new technology with smaller geometries IS digital at first. Then the analog support is added. As Dick said - analog rarely fills up the fab. So it is driven by digital and density.
I suppose you are not in the industry but at school. If not - you can save some $$$ by using M5 MiMcap. To me if you are not using 6 metal layers then drop the MIM down.
If you are ok with extra metal - you can always cover whole area under the MiM with metal connected to GND in order to...
lets consider NMOS. In accumulation your gate voltage should be lower than source potential - so the holes are attracted to the gate and so the capacitor is created between the poly of the gate, positive charge in channel which are divided by oxide. Co that is why the capacitance value is the...
I recommend to run GND line in distance of 1-2um left/right from your CLK line This will shiled nicely the signals parallel with CLK and also minimizes the capacitive load oon CLK line. THEN run PEX with Calibre and run simulation. You should see very well how the shielding works.
I do not like...
a) vias don't carry current laterally. So if you go from your i.e. VDD pad to the transistor (assuming you connect MOS to the VDD rail) you can run big fat metals on top of each other without vias.
b) vias are needed to bring current down to the device and from top metal on io pad to the lower...
What is the length of your clock lines? Will it pass the antenna check?
You could add small driver buffer into 1 line just to see it the issue goes away. I would think that paratitic inductance could be the culprit.
Or you can look into the PEX values and add little LC tank into schematic and...
a) - open to model file and read through it!!!! Also open the little text file which shows how to use tsmc models.
b) tsmc usua;ly provides libraries for core and io (1V and 3V) devices separately. That means in simulations if you want to change all of them to ss you have to change corner for...
If you are in battery powered system like cellphone etc you "ground" connection is the battery - terminal.
In fact you can power whole system that you provide +20V and let say +17V from power supply to the - and + terminals of your pcb - it is all relative. You can also use -20V and -17V if you...
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