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Vco Not Pll

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152 Threads found on Vco Not Pll
The Laplace transform is used for the vco transfer function. Such a function is defined for linear conditions only. Therefore, it applies to the pll under locked condition only - and this is the key for an answer to your question: The pll linear transfer function - hence, also the vco function - is defined in the PHASE (...)
Hi Designing LDO for vco app. At LDO output cap is 2pF. NMOS is used as pass Tx. Load current steps from 0 to 30mA. Pass Tx coming to SAT region after load current reaches 15mA, before it is remaining in Subthresold region. Is it compulsory for NMOS Pass Tx to get saturation at 1mA itself? Thank u in Advance satya
For a vco alone, the jitter is accumulated as the time goes, but a pll don't, is this right? if right, then i want to know if a Frequency Locked Loop can null the jitter accumulation? (FLL is something like pll,and its input and output signals are frequency, so the transfor function for the inner vco is (...)
I'm trying to design a Bluetooth module from scratch. I have experience designing RF (< 1GHz) transceivers from scratch but not ISM. I do discrete design and not IC so planning to use IC for mixer and ADC. I will be designing PA, LNA, Antenna, vco, loop filter, pll and etc. need some advice on where to start. Any (...)
The problem stems from the vco frequency, the pll/MMCM has to multiply the clock up to the vco frequency range and then divides it down again. So to get it up to vco input range means you can't divide it down enough to give you the frequency you want (33/8) MHz. The other method is use only the 33 MHz clock in your design (...)
I've not used Altera SERDES, but designed many SERDES in the 70's (DS1 BER Test sets etc) 1) Normally bit clock vco runs at 2f with quadrature 1f outputs, quadrature (90deg) 1clocks should be available. Pre-Comp, may help improve SNR or jitter reduction, but watch out for ISI and group delay distortion. Plan on doing BER margin
PD selection depends on many parameters, e.g. kind of vco and reference input signals, can be either a bit or word signal, also intended pull and lock frequency range.
Hi, I have a pll target running at 12.5GHz. Schematic top level works. Standalone post-layout vco also works. But top level post-layout pll simulation is not working. I've tried all the methods i can think of: 1. add initial condition at vco outputs; 2. set max. step. 3. add a current pulse injection at (...)
Hi, I am trying to simulate the 4046pll in Proteus. The moment I short PIN 5 to GND and vcoIN (PIN 9) to GND the vcoOUT (PIN 4) keeps on generating 1kHz irrespective of the values of C1, R1 and R2. Please help me why is this happening, i.e. changing R1 and R2 should change the freq at the vco OUT but it is (...)
Hello everyone, i have the following problem: i designed an analog pll, a basic one. Composed by a PFD-CP, a passive filter, a vco and a frequency divider (not programable). The reference frequency is 32.786kHz and the output frequency is 33.5544MHz (N_div = 1024). The corners of the transient simulation are ok, the frequency (...)
I am designing a CW source, and I have to make frequency hopping in frequency range of 1.5GHz~2.0GHz. The main chip is ADF4350, in which a pll and a vco is integrated. The pll works well when it outputs a single frequency number, however, when it is used to hop, there is something spur in the spectrum analyzer. It seems to be the unlock (...)
I'm doing a project to create a pll to cover 2G-7G with LC vco. The process is 40nm and inductance is 1nH. I know the tuning range is a little wide, thus I might use a divide-by-2 circuit to cover the LB and concentrate on 3.5G-7G. But I'm still not certain whether it's achievable to cover 3.5G-7G with one oscillator core. If (...)
I need to generate a sine signal using a vco (voltage controlled oscillator) in order to feed a pll (Phase-locked loop). I need the output to be 12.8MHz and 3.3Vp-p. I bought at RS a vco reference 7099357 Despite the datasheet says: "Output Level (CMOS) O
If i use internal FRC whose nominal frequency is 7.37mhz range .and gives its output to onchip pll (vco range is 0.8 to 8mhz) followed by a prescaler and postscaler ,will it be possible to achieve a Fcy of 20mhz?? not exactly 20 MHz, but e.g. 19.9 MHz. I presume you have a pocket calculator. P.S.: 7.37/7*19 gives 20 MHz rather
Hi, I've designed a pll and simulated it using Cadence Virtuoso ADL. Output of the vco is directly given as a feedback to the reference clock pulse port of the PFD. After some time, the waves ClK1 and vco_out is getting locked. But it is getting off the lock after a while. How can I lock it? Requesting help. Thanks.
Generally speaking, it's not possible without a dedicated pll block which includes an analog vco. There are nevertheless ways to implement a kind of pll in pure digital logic, I guess it win't fit xc9572
Sure, they could do this. Why would they? What's the market, and how big is it? Compared to their integrated pll/vco parts, what would the advantage be?
I think this is a classical pll-vco chain, even if the image does not show the feedback from the vco output to the pll.
Hi All, I am working on digital pll which include vco, frequency divider, TDC, digital filter. I want to simulate the digital pll in cadence. I have the transistor level implementation of all blocks including digital filter. If i include digital filter in the simulation using transistor level implementation, it take long time. Is there a (...)
Sounds vco Pulling Effect because of Doubler. pll may not pull-in the carrier in high pulling effects and therefore vco signal can have some ringings about carrier. I guess an isolation amplifier should be used before doubler.