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## PLL loop parameter calculation

Hi, How to calculate Jitter peaking and 3db bandwidth(in simulation) of PLL across PVT in cadence spectre. Thanks satya

## S Parameter in spectre and ADS

See You can see a defintion of NF(k) in Keysight ADSsim and GoldenGate. If you use more than three ports, e.g, port1=RF, port2=IF, port3=LO, NF(2) is different from NF of cadence Spectre. Here you have to use resistor + vsin instead of port3=LO.

## Discrepancy between simulation results for S-parameter file

Hi I'm not entirely sure if this should belong in this subforum or one related more to circuit simulation, but here goes. I simulated a structure in HFSS and was able to export an equivalent *.s4p file so that I could use it in cadence Virtuoso. However, when I run port analysis in cadence, the resulting s-parameter (...)

## Cadence Virtuoso Monte Carlo Problem

Hi everyone, For an LNA design, the inductors used in the design were simulated in a simulation software separate from the spectre simulator used in cadence for the other components (transistors, resistors, capacitors). So we created a n-port file for the inductors in the design and made it point to the S-parameter file generated by the (...)

## Cadence monte carlo simulation and "multiple" parameter

Hello, Im using cadence 6.1.3 and Id like to do monte carlo simulation. I found out that "m" shouldnt be used in schematic or monte carlo might be errorous. source: So I decided to test it: testbench results

## [moved] S parameter convert to lumped RLC (Cadence)

By extracted the channel to S parameter to simulate, but in cadence the simulation time is huge due to the large s parameter file. Anyone knows some idea that we can convert the s parameter to the lumped RCL circuit to run the simulation? In order words, if we know a frequency (...)

## parametric analyse in monte carlo simulation

Probably by saving your session as an Ocean script and then editing that to add an inner parameter loop. From the menu interface, it's an either/or type choice.

## Using s-parameter for simulation in pspice

The s-parameters being a small signal analysis can be easily calculated using any spice by means of AC analysis. The question is - the mos model you are using for LNA simulation is valid for RF range ? You can refer the application note to know how to calculate s-parameter using pspice -

## input impedance of mixer in cadence

hi thank u edaboard members for helping me a lot... i m simulating gilbert mixer for finding its input impedance i tried it using s-parameter in cadence but the test bench i used have a balun at RF port so while measuring Z11, i think it gives input impedance at single ended input of balun but i want to measure input impedance at mixer input

## Extracting device parameter of an non-conventional FET and use it in Cadence.

Hi, I've been assigned to design a non conventional FET (FINFET,Quadfet etc.) in silvaco and then somehow extract and feed the generated device parameters into cadence for making a single stage amplifier. I wanted to ask if it is possible?? and if yes then how it could be done?? Thank you very much in advance:)

The source which you have used is wrong.It's a AC source and cannot be used in s-parameter simulations. You have to use "psin" or "port" element instead of it.These components have internal source impedance ( e.g. 50 Ohm by default) and you should define this component in s-parameter simulation setup ( if you do 1-Port (...)

## I have this error on cadence , any help ?

You would like to redefine a parameter which is already defined in your model file or PDK. You add this parameter to 'Design Variables' pane in Analog Design Environment window. When you run the simulation, you get an error message similar to the one above. Does Spectre allow duplicate parameter redefinition? Spectre (...)

Sure.. Assign a variable for the parameter which you're interested in then do your simulation by sweeping this variable. For instance, Rload=1K (Initial value) then make it as sweeping variable in ADE.

## Can cadence NCsimulator initialize unresetable flip/flops?

Hi, does NCsim provide some kind of simulation switch/parameter to initialize all the unresetable flip flops of the design, instead of leaving them undefined (or X)? Regards, Giorgos

## cadence cannot plot after simulation

can anyone help me,please!!!!when use the spectre to simulate the SP parameter,after i finished the simulation,and wanna produce the plot,the plot cannot be openned,and the error like this: Loading paraplot.cxt simulate... Loading viva.cxt INFO (ADE-3071): simulation completed successfully. reading simulation data... (...)

## inductor s-parameter simulation

inductor s-parameter simulation in cadence While setting the parameter of the inductor, it says "Inductance:1nH Resistance: 670m ohm Capacitance: 240fF ". But the s-parameter simulation shows that the real part of Z11 of the inductor is 1.76. Could anyone help me and explain it to me? (...)

## Plot gm/id vs (id/(w/l)) curve in spectre-cadence

Hi, You can do it from dc analysis. In sweep parameters choose the "component parameter" position, like this: 88817 Run simulation and now you can plot transconductance curve vs w or l of transistor.

## confused with build-in parameter in CDF and parameter in .scs

what's the difference between the job of cdf parameter, which can be set manually in cadence build-in dialog window when try to "i" an part on the schematics, and that of simulation model file, like .scs, which is loaded in the procedure when try to do spectre simulation? Maybe some parameters are (...)

## Can I do "if" "then" in Cadence expression?

Well, there's the analogLib switch element which, if SW was a node voltage, would do what you want. Not the form you ask for, but the result. And it wouldn't look for strict equality, but >= the threshold parameter. You could stack switches, like relay logic, to get closer to an = function (arbitrarily so, but finite slop).

## ft of PMOS tsmc 0.18u technology

I use AC and S-parameter simulate the ft of NMOS and PMOS in cadence spectre, two kinds of simulation results, then use ft = gm/(2 * pi * Cgg) verify , found simulation of NMOS and calculation results is same, calculation results of PMOS are much smaller than the simulation results, I can get gm, and Cgg (...)

## How to add Antenna S1P parameters in Cadence Spectre and plot the S-parameter gain

Hi, I have to simulate the gain of my designed LNA with certain antenna impedance as a source. I am using cadence spectre for the simulation. The problem is that cadence spectre provides n1port for importing S11 parameters of antenna, which is a passive port. Therefore, if i connect the n1port at LNA input to represent (...)

## How to plot the Q of a filter from the S-parameter simulation with Spectre

Dear all, I have run an S-parameter simulation with Spectre in cadence and got the S21 of a filter. Can anybody tell me how to plot the Q, which is defined as 3.14*freq*d(phase(S(2,1)))/d(freq) BTW, the differential term in that definition is also called Group Delay. My friend told me to export the data into MATLAB and plot the Q. I (...)

## How should I perform this simulation in cadence

Use the parametric tool where the digital code is your parameter.

## Error in sp analysis: could not find the shared object libsparam

Hello, I beginner in cadence, help me please. (sorry for my English) When doing the s-parameters simulation I get such log: ****************************************************** S-parameter Analysis `sp': freq = (100 MHz -> 1.2 GHz) ****************************************************** Error found by spectre (...)

## how to find the expression for freq in S parameter simulation?

Hi Guys I need to find the expression for freq for further calculation. I just can not find the expression for it. I am using cadence 1.5.1 and spectre. I remembered I used to find it in browse the data, then I can find it from variable, but I just can not find it now. Thanks

## How to import CST or HFSS result into Cadence Spectre?

Use S-parameter of Touchstone format. The Designer's Guide Community Forum - conversion of .s8p into SpectreRF netlist

hello! If for one transistor k=1/2(uCox) then which parameter in cadence is Cox and which is u (mobility)? An lambda? Can't find them. thx

Hi All, I have a question related to cadence....After i do the DC sweep simulation, I want to plot the variation of some parameter vs any parameter..the cadence won't let me choose this option. It plots "vs" the default swept value. Eg: If i sweep W (width) of a device and now if i want to plot gm/Id vs Id, (...)

## help with transient analysis of a vco in cadence

use parameter "max step" to define maximum simulation step (e.g. max step = Tosc_period/10), and "trap" method of integration

## [cadence newbie] plotting model parameter

Hi aindejeje, 1.Create a file (with any text editor) with .scs extension (for example sigtype.scs) and in this file write the following : save * sigtype=all 2.Include the above file you just created to your model files from the ADE L environment. 3.Run the simulation with your custom swept parameter and via

## Measuring the on-resistance of a pmos in triode region

Hi all , i want to measure the resistance of a pmos (operating in triode region) in cadence and i want you to suggest me a practical way to do that.I am quite amateur to this,although i used s parameter simulation i didnt have any results. Thank you in advance

## monte carlo simulation in tanner............plz help me

I don't normally use Tanner, although I have done briefly. I cannot see from your netlist how the Vto in the model file would be overridden by what you have done. Is Vto_n defined as a global parameter in the model file? Keith

## what is the Vd(sat) parameter

Hello all,my question is : what is the Vd(sat) parameter in cadence spectre simulation results??Is the Vds that a cmos transistor must have in order to enter the saturation region and it means that a designer must be carefull to have Vds=Voverdrive + Vdsat for nmos transistors to operate in sat region?? A second question is : Can somebody (...)

## S parameter Simulation in Cadence Spectre RF

when we do spp (S parameter simulation) in cadence Spectre RF"spp" is not SP analysis. "spp" is a conversion program of HSPICE netlist to Spectre netlist. And SP analysis is a function of Spectre not SpectreRF. so, in Sp

## S parameter Simulation in Cadence Spectre RF

hi Guys, can anybody tell me ? when we do spp (S parameter simulation) in cadence Spectre RF and we have to plot S11, S12, S21 and S22. we have to choose dB20 with rectangular mode and there is one more option below in that window to choose Power Gain P with dB10. so, in Spectre RF when we plot S21 with dB20 . then is that mean (...)

## How to plot MOSCAP C-V curve using Cadence Spectre in ADE?

for moscap, C-V fullfill the formular: V=I*Z=I/(jwc) , so |C|=|I/(w*V)| if V=1,w=1 then C=I Insert a dc voltage source in the gate of moscap, set the "ac amplitude" to 1 and dc voltage to "Vin". Do ac simulation and sweep the parameter of Vin from -2V to 2V at frequency "1". Plot ac current "I" of the terminal "G" and the C will be the same as

## Simulation of active inductor on cadence

Thanks LvW! But can someone also point out if the method I am using is correct? As in doing the S-parameter analysis, and then using the Z paramater. Or is there some other way? It's ok, but since you connect one terminal of inductor to ground, so it's just a single-ended Q if you use it as a differential Q or some el

## how bsim4 model works? Transfering parameters question

Hi Guys For most of the device, cadence use bsim4 model, so how in cadence they transfer the parameter into a real circuit like capacitor , resistor network. Also, how will they use I-V curve of device? Will they use it to calculate capacitor and resistor and inductor, or they will use I-V curve directly to run the (...)

## How to run RAN and PSS simulation in CADENCE with the nport

I try to run the TRAN and PSS simulation in cadence with the nport s-parameter file obtained by HFSS.But it does not work. How to run TRAN and PSS with s-parameter?

## Spectre simulation problem: Unknown parameter

Hi~ I use the IBM 7RF cadence designkit with cadence 5.1.41 and spectre simulator.When I try to simulate a simple circuit using the nch mos devices then I got following error: ---------------------------------------------------------------------------------------------- Error found by spectre during circuit read-in. ?/cad

## cadence simulation - Vth of a MOSFET as a parameter

How to specify Vth(Threshold voltage) of a MOSFET as a parameter for monte carlo simulations. Thanks in advance.

## Weird gm/id vs vgs result in Cadence

you can also use dc analysis and obtain 'gmoverid' parameter.

## What is the parameters for calculating of AMS CXQ 0.8u

What is the parameters for calculating of AMS CXQ 0.8u such as Vthn, Vthp , Kn, Kp. Lamda and so on. I use cadence simulation.

For your first error, there is some CDF call back function working in the background that will try to calculate some parameter like Perimeter of Drain region or area of drain region. When you dont enough parameters for that callback function it displays an error in the schematic window. To confirm about your simulation you need to look at (...)

## The equation for beteff parameter in Cadence Spectre

Hi can some one tell me the equation for beteff parameter that is displayed in cadence spectre? Thanks

## How to run Montecarlo simulation in Cadence for tsmc 0.35 um

Hi, I am a research student in ASU, Tempe. I am having troubles in running the montecarlo simulation in cadence, for tsmc 0.35 um technology. Looks like some parameter files and parameters are not available. Can someone, help me in this regard or upload the required files for running the simulation?? (...)

## Have someone ever used the dcmatch analysis in cadence?

I am trying to simulate the mismatch of current mirror using spectre-dcmatch. Now the problem is we do not have the parameter in the model card. So I mannully set the parameter mvtwl. However, in the DC simulation I still can not see the modified parameter, and it only displays zero. Can someone help me? Thank you!

## how to get the node capacitance and resistance using spectre

First, you should using verification tool diva, dracula or calibre get the extracted file, and annoded the parisitic parameter. I know the cadence cdsdoc include some paper refer to it. you can read it

## cadence urgent help for sw cap ckt!

By parameter sweep.