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Gilbert Cell Multiplier

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19 Threads found on edaboard.com: Gilbert Cell Multiplier
I am a first time analogue designer and need help with my gilbert cell multiplier(CMOS 0.18um technology). The problem is that my circuit doesn't bias correctly.I work in low frequency. the output that I need, the plot of four quadrant of multiplier. *gilbert cell analog 5 .options (...)
Are you using the differential output? I did a quick simulation of a bipolar gilbert cell mixer IC I designed a while ago and you get massive clock feedthrough if you don't look at the difference between the two outputs. Keith
A common way to do analog multiplication is with a gilbert cell.
Hi, Can you please tell me - the difference between gilbert cell and four quadrant multiplier? - what will affect the output frequency in four quadrant multiplier. i.e. the output frequency will be a multiple of both input or division of them? Thanks, :)
Changing the current through R2 should change the BE impedance of Q1 & Q2, which changes the gain. That is the principle behind a gilbert cell mixer. You only have half a gilbert cell so you are unbalanced and will see some DC bias shift as well. It is possible the BE impedance change is swamped by R3 diminishing the effect.
Hello, I am trying to plot the ac response of a gilbert cell multiplier. I have set the differential pair inputs as V1 + v1 and V1 - v1. For the quad transistors, I have given V2 + v2 and V2 - v2 as inputs. To perform ac analysis, I have set the quad pairs ac magnitude as 0 and the diff pairs ac magnitude as 1, now after performing the (...)
I fear, the term voltage controlled amplifier isn't very clear. I presume, you are referring to a variable gain amplifier (VGA). It comes in different flavours with rather different specifications regarding bandwidth, linearity and dynamic range. The classical building block for VGAs is a gm multiplier respectively a gilbert cell, comprised (...)
gilbert cell is a frequency multiplier i.e. If my LO signal is at frequency f1 and my RF signal is at fr
an arithmetic divider that operates ideally at any frequency Keep on dreaming. From the existing analog multiplier/divider variants, only "gilbert cell" (gm multiplier) is wideband. Log/antilog offers higher dynamic range but is restricted to MHz bandwidth at best, hall sensor multipliers (rather (...)
This paper is implemented using a W/L of 10/30 and now we are trying to implement it using 0.5 um AMI technology. What least value we can assign to W/L..? Please help...
Hi All, Let me mention another method for a frequency doubler circuit, apparently neglected by many people, which is a four quadrant multiplier or known as gilbert cell. If you connect the two inputs together and apply a sinusoidal input, you will get a DC term + a double frequency sinusiodal voltage at the output. It is nearly as wid
my design is to replace PLL to get a 50% duty design include a gilbert cell as a frequency multiplier follow by a frequency divider(divide by 2 -D flip-flop) jitter problem for input is input is just a pulse wave(~48Mhz) so phase lock i ignore my question is .. is this simple design will be succcesfull? is this comb
If you fed the same signal u(t)=U*sinωt to both inputs of the gilbert cell, it will multiply the two signals. Therefore, you will get: Uo=U^2*sinωt*sinωt=0.5*U^2*(cos(ωt-ωt)-cos(ωt+ωt) The term cos(ωt-ωt)=cos(0)=1 represents just a DC component. But the term cos(ωt+ωt)=cos(2ωt)
Well, a mixer and multiplier are of same type of architecture. The function realized by a multiplier and the mixer are the same. So, you must be using Spectre for simulation which is fine. Usually people use single quadrant gilbert cell type.
Please specify your questions. there are lots of application of gilbert cell in Analog IC design, especially in RF part.
Search for current mode blocks like current conveyor and gilbert cell. Should give you a better idea on what's current mode as well as multiplier.
Hi, razavi's classical analog IC book talks about it, the common used one is gilbert cell, you can also search in google to find papers.
Hi Faisal, 1- frequency multipliers are used as signal generation technique, permeting one to abtain and utilize the harmonics of a fundamental frequency technique, meaning if your input frquency is "f" you can get 2xf or 3xf ... 2- one of the approches that is been used for analog divider and multiplier is gilbert (...)
Search for paper by Razavi or Abidi online or at their UCLA website. They wrote quite a considerable amount on gilbert multiplier.