18 Threads found on edaboard.com: Cv Curve
can any one tell me hw to plot CV curve of a simple nmos using cadence?
means hw to go abt.?
Analog IC Design and Layout :: 20.09.2007 06:01 :: sachinmaheshwari :: Replies: 0 :: Views: 673
You can't modify the varactor CV curve, but the overall circuit circuit characteristic.
You need to redesign the tuning circuit so the varactor is directly coupled to the LC circuit and recalculate the LC values to cover the domain. You may try to minimize the voltage on the VCO LC tank so the AC voltage on the varactor is much lower than 1V and i
RF, Microwave, Antennas and Optics :: 24.01.2008 07:49 :: Eugen_E :: Replies: 2 :: Views: 852
I did In CADENCE. I swept the gate voltage and shorted the Drain, Source and Bulk terminal to GND. I did the DC analysis. Now I want to plot the CV curve. But I don't know how to do it??
Please can anybody tell me the way how to do it in CADENCE???
Is it ok to do it in DC analysis? I think the capacitor's val
Analog Circuit Design :: 28.05.2011 19:30 :: enchanter :: Replies: 5 :: Views: 2530
Bias the MOSFET use DC voltage source as you want, remember to insert a large inductor between the DC voltage source and your drain, gate, source etc. After this, connect a 1V AC source to the gate, perform a AC simulation on the frequency range you care, then plot out the current flow through this AC voltage source, since the AC voltage is 1V, the
Analog IC Design and Layout :: 05.10.2005 09:26 :: pi331133 :: Replies: 3 :: Views: 3609
Connect in series 2 DC sources:
One of them has Vdc=Vgate Vac=0
Another Vdc=0 Vac=1m
Use AC analysis and change Vg as sweeping parameter.
Then plot C= Ig/(2*Pi*Freq*Vgs) vs. Vgate. You will get CV curve.
I did that several times in Cadence. It works fine.
There is another method using transient with fixed frequency.
Analog IC Design and Layout :: 12.09.2006 06:46 :: Fom :: Replies: 4 :: Views: 2923
u can plot the capacitance , by using s parameter simulation or ac simaltiuon
just sweep the control voltage
and get the input impedance , the imaginary part is equal 1/(2*pi*f*c)
u know f then u can get C
or in hspice manual there is anonther way to polt Cv curve of search there
Analog Circuit Design :: 08.05.2005 14:06 :: khouly :: Replies: 2 :: Views: 643
i know maybe it is convinent to simulate by using ads
and i want to know how to do that in hspice,
to simulate varactor is it by using "LX" ?
RF, Microwave, Antennas and Optics :: 24.05.2005 03:20 :: gargoyle :: Replies: 0 :: Views: 996
the tuning range of the VCO depends on the CV curve of the varactor , so to get high tuning range u need the vacattor to have wide tuning volateg
Analog IC Design and Layout :: 17.04.2008 04:15 :: khouly :: Replies: 6 :: Views: 1090
I tried to build a veriloga model for varactor and the code is listed below.
I used a math equation to fit the CV curve from the foundry (from -1.8V to 1.8V).
But when I did the ac simulation to double check the value in the equation, I got two different CV curve.
Could someone help me?
Analog Circuit Design :: 16.09.2008 03:55 :: desperado0729 :: Replies: 3 :: Views: 1152
I am designing a broadband micro strip patch antenna in ADS (resonant freuency fr: 10GHz) . I have the narrow band resonating structure ready with me and now I would like to broadband it by connecting var actor diode near the edges. I would like to know how to stimulate a varactor diode in ADS.
I have made the circuit as in the attach
RF, Microwave, Antennas and Optics :: 11.04.2010 18:31 :: nnayak82 :: Replies: 1 :: Views: 1221
How can I measure Vth of an NMOS in a lab? I had read that I can plot the square root of the drain current vs. gate voltage (Vg) and then take the intercept of the line on the Vg axis. Can the CV curve also be used to measure Vth?
Also how is Leff (channel length) and width measured?
Analog IC Design and Layout :: 14.06.2010 19:33 :: design_oriented :: Replies: 3 :: Views: 1048
Look at Fig. 4.4. (C-V characteristic of a poly/n-well MOSCAP) in the PDF below. The deep depletion region is the range in the depletion region, where the low frequency CV curve is at (or close to) its minimum, or - in short form - the center part of the depletion region.
At the min. value of the CV curve (in the cente
Analog IC Design and Layout :: 18.06.2010 10:42 :: timof :: Replies: 9 :: Views: 5031
I plot the CV curve in following way with AC analysis.
Initiate the ac analyis at one frequency and vary the control voltage. Plot the CV curve of MOS varactor (e.g at 1GHz) using the following formula.
(-1 / (2 * pi * 1000000000 * imag(VF("/out"))))
See the circuit diagram attached with the msg. 100H ideal inductor is there to
Analog IC Design and Layout :: 02.05.2011 04:15 :: viperpaki007 :: Replies: 5 :: Views: 1671
There are a number of solutions;
You can extract a CV curve using ATLAS and sweeping the voltage and defining the steps. You could then consider plotting 1/C^2 vs voltage to extract the threshold voltage.
Alternatively both ATLAS and ATHENA allow you to extract the VT voltage directly, which you could also conduct for comparison.
Finally, I assume
Software Problems, Hints and Reviews :: 10.07.2013 10:32 :: Kenneth_Potter :: Replies: 1 :: Views: 826
I think the spec is kind of strange, since I=Q/t, mA/hours is a wrong unit
they already told you Q=CV,
Analog Circuit Design :: 28.07.2007 14:12 :: waxtomato :: Replies: 4 :: Views: 1124
The CV characteristics of 2 RVT & LVT varactors are just offset by the difference of their Vt voltages.
Analog IC Design and Layout :: 22.09.2008 17:30 :: erikl :: Replies: 4 :: Views: 1707
Dr Ayman , I also tried alot to get training in analog design and i've failed , I'm graduate from El shorouk academy , Electronics and communications , and i read many books in EE ,like art of electronics , Razafi's books , and really I'm dissapointed with no chances in training us , would you like to let us have training?
EDA Jobs :: 03.09.2009 16:31 :: andreahmed :: Replies: 9 :: Views: 2866
I'm trying to understand the differences/similarities between the Exponential curve that represents a controlled change in Frequency and the Logarithmic curve that represents a controlled change in Volume.
My understanding is that the human ear responds to changes in Frequency in an Exponential manner. e.g. In Voltage-Controlled synths using the
Mathematics and Physics :: 23.02.2012 07:25 :: juz_ad :: Replies: 1 :: Views: 689