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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.

## 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? (Power gain can be added as an expression in the calculator) If not, what's the correct way to get 3dB bandwidth by in cadence Spectre Virtuoso?

## 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