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256 Threads found on Guard
No need to make a guard trace between pin 2 and 3. A critical point is the creepage path between pin 2 and 3 (V-) on the package surface. For critical applications use an electrometer OP with alternative pin layout like OPA129. Should I remove ground plane bellow this input in order to minimize parasitic capacitance on this pin?
Hi I am designing a capacitive touch switch board using CAP1298. It has been mentioned in the datasheet that the CS5 pin be used as a signal guard. In my PCB, i have included the signal guard around all touchpads on oneside of the board. Should i place the signal guard on by board's bottom also, or simply is it enough on one side alone?
If you are after minimum supply induced noise in a (say) RF amplifier, you might connect the deep NWell to substrate potential, and the PWell's guardring or tap as well. This will give multiple layers of Vss-referred capacitance with no real supply coupling path. If you tie DNW to VDD and PWell to VSS then you have a large-ish coupling cap to the
Some parameters of your specification don't fit well together. A differential current source can be hardly implemented without finite common mode impedance. Achieving nA signal magnitude, ns rise time and 300 V common mode voltage at the same time sounds unrealistic. At least need a third terminal acting as signal ground or guard potential. You
There will be no "repulsion". Outside the depletion regions the substrate is field-free. Depletion regions are "sinks" for free minority carriers because any that diffuse into the depletion field will be swept to the appropriate contact. guardrings also improve shunting resistances which is the main thing for latchup suppression. They also by t
for analog you usually have lots of power concerns and interaction concerns (such as guard rings). it is likely that the analog blocks do not use the same power source of the digital parts and floorplan has to especially take that into account. analog usually requires pads that are specific for analog, and you will most likely want to place the ana
I'd suggest 3rd ring (n+/dnw) : float/VDD 2nd ring (p+/pw) : 0 1st ring (n+/pw) : float/VDD A VDD connection of the n+ guard rings can raise the whole VDD net well above its normal voltage level - which can absorb a lot of energy during ESD breakdown - if not the VDD protection itself limits this voltage too much. In this latter case, float
Hi, Confused about the order in which ptap ring and ntap rings used in double guard rings. which one should come in the outer region ? and which one should be inner? and why? I read both way (either p+ outside or n+ outside). Please explain with sufficient reason and why not the other method? If both ways we can use please mention the scenario.
If you go to slide 13 of that set, what he calls "level shifter" is what I would call the cascode "guard" devices (as opposed to the cascode "masters", your current mirrors) in a cascode mirror stack. I doubt my nomenclature is popular but have seen none I like better.
There is a design philosophy called "mobetta"... If you want to extract minority carriers from Nwell then you need some P+ plugs there. PMOS S/D might suffice, but walling the Nwell with N+ outside P+ would ensure that any carrier trying to diffuse in, would hit that getter junction depletion region and sweep out. Maybe you could show a picture o
Preethi, P diffusion guard ring means the ring with active layer, p+ diffusion layer, metal1 and contacts i.e basically its a P+ substrate pick up in the form of ring. You can get diffusion rings by using create--> multipath part or create--> guard rings in the cadence virtuoso/icfb. Press F3 and change the type of ring that you want to create.
hello! I am new to HFSS and am not sure how to excite my capacitor structure. It is a cylindrical capacitor (plates along the curved edges of the cylinder). I am stumbling on how to excite it, as I have 3 electrodes. I'd like to be able to have the high electrode at +V/2, low at -V/2 and the guard electrode at 0 or +V/2. Is this possible?
I view that difference in resistance as trivial, and probably due to the operating point differences between wide swing and classical cascode operating points. The Vds is likely partitioned differently and my gut feeling is that the classic version has the guard (upper) running with lower Vds, so closer to linear and less improvement to Rout. You m
What is more important for EMI shielding effectiveness with respect to guard traces and via fences, the width of the copper trace that circles around the area or the distance between the vias to ground that connects to the trace and the other ground planes? Are both equally important or is one important and the other not so much? Any good web re
Thanks for replying! I find a tutorial for IBM process. It is useful Hello kky1024, I have the same problem with the chip edge and chip guard ring. Could you share the "useful IBM process tutorial". Any body have another reference? Thank you!
Hello, For nmos, usually guard ring is connected to a separate and quiet GND. But in this case, the source and bulk are not at the same potential. So there will be body effect that has influence on vth. So the guard ring reduces substrate noise, but increases body effect, am I right? For analog design(like a PLL), if the current is very smal
Concentric guardrings are common in ESD related circuitry (pad cells etc.). One useful function is that the built-in depletion region is a "getter" for loose minority carriers in the substrate. The ring can also kill lateral BJTs' base ohmically and deterministically if it is closed / pervasive, fight field oxide inversion / charging and so on.
Hello all, For my specific problem I need to increase some PMOS NWELL sizes from the PDK transistors. In my simulations I always used 5 terminal PMOS (S G D B PSUB) devices. However in the layout, there is already a guard ring around the nwell, leaving no option to draw a bigger NWELL. I tried to use a 4 terminal PMOS (without PSUB) in lay
Hi guys, Because I have some space left in the layout of my comparator, I thought that I could fill that space with contacts, in this case I am referring contacts to the n-well. Is that ok? You can see the picture bellow: 112730 Thnks in advance.
What type of conductor you have used for guard ring ??And why you have used a guard ring ?? What is its purpose ?? How you have simulated Q factor, which set-up you have used ?Two port s-parameters or one port is short circuited ?? You have to mention some details...