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17th June 2019, 14:23 #1
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measuring the parasitic capacitance at a certain node in cadence
is it possible to measure the parasitic capacitance at a certain node in a schematic in cadence??

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17th June 2019, 16:37 #2
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Re: measuring the parasitic capacitance at a certain node in cadence
Yes, it is.

17th June 2019, 17:51 #3
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Re: measuring the parasitic capacitance at a certain node in cadence
I don't know what you want to mean by "in a schematic in cadence" at all.
However Synopsys HSPICE have following.
Code:.OPTION CAPTAB Adds up all the capacitances attached to a node and prints a table of singleplate node capacitances. Syntax .OPTION CAPTAB Default 0 Description Use this option to print a compiled table of singleplate node capacitances for diodes, BJTs, MOSFETs, JFETs, and passive capacitors at each operating point. Note: When .OPTION CAPTAB is used to estimate the equivalent capacitance of the circuit nodes, HSPICE can give a zero capacitance values for some nodes when a resistance is connected to that node. The reason for getting 0 is that the capacitance is a dynamic, frequencydependent capacitance and not a static capacitance. You need to run an AC analysis to see a nonzero node capacitance.
https://www.edaboard.com/showthread.php?380999Last edited by pancho_hideboo; 17th June 2019 at 18:01.

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17th June 2019, 18:37 #4
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Re: measuring the parasitic capacitance at a certain node in cadence
can you please tell me how to find the parasitic capacitance in cadence IC 6.1.3
   Updated   
i have connected a circuit in cadence and i want to know the value of the parasitic capacitance at this node
my question is wither there is an analysis that could give me the value of the parasitic capacitance at this node?

17th June 2019, 18:53 #5
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Re: measuring the parasitic capacitance at a certain node in cadence
If you include adding minor schematic mods, then I prefer
to add a shunt pulsed current source, who can inject a
known small charge (large enough to be seen, small enough
to be smallsignalish) and look at the node step voltage
right at the end of the pulse. Q=CV.
Any "on" elements will steal from step voltage and you may
want to apply a little work at determining what went to R
and what went to C.

17th June 2019, 19:03 #6
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Re: measuring the parasitic capacitance at a certain node in cadence
What do you want to mean ?
Describe correctly with correct terminology.
If you use Cadence Spectre, use "info what=captab" analysis in Cadence Spectre.
Surely see https://www.edaboard.com/showthread.php?380999
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17th June 2019, 20:11 #7
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Re: measuring the parasitic capacitance at a certain node in cadence
What would you like to do?
1. Simulate capacitance at specific node?
2. Extract capacitance for all nodes?
3. Read parasitic capacitance from extracted view?
What views you have?
What tools you have?

17th June 2019, 20:47 #8
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Re: measuring the parasitic capacitance at a certain node in cadence
Mandatory reminder that Cadence is a company. There is no tool called Cadence...
Really, I am not Sam.
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