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## Cadence calculator: use actual sweep value

Hi! I want to evaluate an expression with the calculator in cadence. I do a sweep over a variable called "delay_stop". I want to see the actual y-value (voltage) of a pulse signal on that sweep-step. For example: value(VT("/Q1") "delay_stop" 4.738693e-09) Q1 is my signal and 4.738693e-09 is one time i clicked in the (...)

## Comparator Gain simulation - cadence

... until a start to get the same gain (128000) no matter the step I use (lower). It kinda like stabilizes. This for a sweep from 1.6485V to 1.6515V with 0.01uV of linear step. Due to positive feedback you get a rather steep gain peak at this voltage - you should see it if you plot gain vs. this input voltage. Th

I'm doing DC sweep simulation with cadence 5141. Now I've got V1~VX plot and V2~VX plot, from which I want to obtain the V1~V2 plot. How to do this? I know that this is possible through exporting the data to MATLAB or Origin and replot, but can I do it with cadence spectre? (...)

## plot the curve of Cgs vs Vgs in Cadence

Hi, Follow the steps listed here : Everything until step 6 will be similar. Then choose Cgs and if you sweep VGS, you'll have your plot. Credits go to the writer. Natnoraa

## bandwidth plot of downconversion mixer using cadence

hi i have designed a downconversion mixer, i hv measured conversion gain, noise figure, linearity but not able to measure bandwidth or freq range of mixer. i tried PSS + PSP but in this only IF freq i m able to sweep but did'nt get the option to sweep RF frequency. can any1 suggest me wat to do

## Subtracting a plot from its x axis

Hi, I need to plot the difference of a curve with its x axis (which by the way is temperature, my DC sweep variable). Is there a way i can do it in cadence 6 calculator.

## Plotting against the sweeping variable

Hi, I am running parametric simulations in cadence 6. I am running transient simulations while sweeping a bias current in my circuitry. This means I am getting plots of Voltage vs time. I now want to plot the variations in voltage with respect to my sweeping variable, the bias current, to know if the (...)

## Plotting gm vs temprature for constnat gm bias ckt

Do a dc sweep set to sweep temperature in ADS and then use the results browser to locate transistor output parameters. Thanks, but I am not able to plot gm even after doing temperature sweep,can u please explain in detail.

## temperature vs frequency plot in cadence

I've never tried to sweep temperature, but I often use Parametric Analysis to step it and plot stuff. Perhaps the problem is in getting frequency as a scalar value. My version of Calculator has a freq function that can be used on transient simulation results. I have also used a veriloga "widget" to generate a voltage proportional to frequency. Ma

## 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.

I'm doing simulations on a VCO using cadence at the moment (relative n00b to cadence). I've got my circuit functioning and have a plot of the transient performance of the circuit for a set control voltage. What I'd like to do is sweep my control voltage and generate a plot of voltage vs. frequency. At (...)

## gm measurement plot in OTA in CADENCE 6.1.4

Hi Rajeshree, setup up your testbench such that your OTA is in unity gain Feedback. Run a DC sweep and measure the output error current. you can connect your output to a current mirror source/sink (it depends on your transconductance design). Change in o/p current wrt change in i/p V is your Gm of the whole circuit..

## DC Gain Measurement using STB in Cadence

Does anyone know of a way of extracting more information from an STB analysis in Spectre than appears on the Direct plot menu? I need to measure DC (ie low frequency) gain, 3dB point and the phase at an exact frequency. Clearly I can do this using cursors, but that's not a great tool for Monte-Carlo, worst case or parametric sweep simulations. I've

## Help me with Monte Carlo analysis for SRAM

scatter plot in matlab or octave: plot(x,y,'.') In cadence I don't know exactly. There is a command "plotStyle('scatterplot)" you can type into the icfb. But how exactly you choose series I don't know. I guess the 'x' would always come out as first sweep variable .. ---------- Post (...)

## How to get 3dB bandwidth of a Class E PA in Cadence Spectre Virtuoso?

For a nonlinear Class E Power Amplifier, if I want to check its 3dB bandwidth, do I just do a parametric sweep analysis of frequency of the input signal and see the frequency vs power gain plot?Use PSS Analysis with sweeping fundamental frequency which is a frequency of driving signal.

## how to find gain of an opamp@cadence

DC sweep the input voltage and look at its derivative.

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 (...)

## how to plot a load line on Id~Vds curve

Save terminal current of MOS device and make the voltage source sweep and plot it..

## help:how to plot the gm*ro vs Vds curve with cadence?

Hi afujian, First of all you will perform a dc sweep for Vds.Then from ADE L environment you will access the top menu and find the Results Browser (Tools-->Results Browser).From there you can plot the curves gm vs. Vds and gds vs. Vds independently,where gds=1/ro.After that,you will have those plots in different waveform windows and you (...)

## HOw to plot id vs vgs for different channel lengths.

in analysis choose DC sweep for Vgs, and then do "parametric sweep" for L variables

## Plot NF vs QL in Cadence

Does anyone know how to plot NF vs QL in cadence where QL=1/(Rs*Cgg*Ωο)? I did the following simulation steps: 1) I defined QL in calculator window 2) I ran a Noise Analysis simulation at 5Ghz (sweep Variable=Vgg 0->1.2) 3) I plotted both NF vs Vgg and QL vs Vgg at the same graph windows and then (...)

## Sweep the delay between occurrence of two signals in cadence

Hi everybody I want to plot clock-to-output delay for a D type flip flop versus input-to-clock offset in cadence to measure flip-flop setup and hold time. something like attached picture. In fact I don't know how to sweep the delay between occurrence of the edge of data and clock signals in cadence. I use spectre for (...)

## Ploting cgg Versus Voltage (Vin) with Cadence

Hi members, I use a dc source and I sweep Vin. Could someone tell me how to plot cgg Versus Voltage (Vin) using cadence+Spectre ?

## 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

## OTA sizing by gmoverid approach

I think 1st just try to plot the gm vs the Id sweep that you might be doing. Check if that is working. Once that works, then plot gm/Id vs Id. That should give the same shape as the one they have in the paper. If that works then in cadence if you plot both gm/Id and Id/(W/L) then on the waveform window (...)

## Define Vov=Vgs-Vth in Cadence Calculator

there are so many manuals that come with cadence IC. read the one regarding wavescan and you will learn it is not difficult to create an equation, plot it in a sweep then plot another variable against it.

## gm/Id Vs Vgscurve of a mosfet

Run DC analysis. sweeping variable is Vgs (just connect Vgs to Vdc and sweep Vdc voltage). Then using calculator take IS of drain or drain current. Click "Special function" and select "deriv" Then click "x<->y", then "/"(devide) and "erplot"

## How to plot CV curve for a MOSCAP in Cadence?

you can simulate in ADE, sweep the gate voltage as a parameter!

Hiii, How to plot the conversion gain and noise figure as a function of LO square wave amplitude in specter? thanks in advance..... Use PSS/Pnoise of SpectreRF with sweep of LO amplitude.

## how to plot Vth vs Vgs in cadence

Operation Point Analysis in cadence can gives u only one value for Vth parameter. U don't able to plot Vth vs Vgs during DC sweep. Simple way to do it is using Parametric Analysis. U need to set DC OP analysis, output variable e.g. "Vth" == OP("/M1","vth"). Than u can do Parametric Analysis with sweep over Vgs. U hope u (...)

## Sweep of size in transient analysis-|CADENCE?

You can set W or M-factor as a variable. Then run Parametric analysis. Select variable to sweep, set FROM and TO, number of steps. After analysis will be over use calculator fuction delay. It will plot Delay vs Parameter (or Variable).

## help: how to plot gm-vs-vgs in cadence wavescan

Gm is Operation Point parameter. U can get one value of Gm for given Vgs value when u do DC Operation Point Analysis. Such way u can't sweep Vgs, so using cadence/SPECTRE u can't plot gm-vs-vgs drawing. If only u've got familiar with OCEAN/SKILL. Another way to plot gm-vs-vgs is to do AC sweep. U need to (...)

## THD versus input amplitude

THD is run in transient simulation. you can sweep the input amplitude to get the THD. Then try to THD vs input amplitude with other tools

## How to plot the parameter region after DC sweep in Cadence?

hello, i want to check when a MOS will enter linear region cannot i plot the parameter region after DC sweep

## Is every Spice model suitable for plotting gm/id curve?

since gm=dId/dVgs u can sweep Vgs and plot Id versus Vgs and u get gm from the slope of the plotted curve

## How can i plot vth vs L in cadence? (NOT vtho)

You can plot Vgs at max gm using calculator special functions. Use DC analysis with Vgs sweep and parametric analysis sweeping L as parameter. Then plot xmax(deriv(Id)). It will plot Vgs at gm max vs. L.

## question: deviation of Vth

Or run a parametric sweep first , Goto the 'results browser' and find the transistor and click on vth to plot it. (using cadence tools that is)

## Plotting lambda and Kappa in Cadence

how do you get lambda and Kappa (u_nC_ox) of a transistor and plot it against some sweep variable? Any suggestion will be helpful. Thanks