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113 Threads found on Charge Pump Phase Phase
Hi, We are getting the current from charge pump and then we converted it into voltage and the again into current. What is the use of this procedure. Are there any advantages. Normally a digital PLL has a phase comparator and an integrator with lead/lag compensation RC network to drive the VCO. Using a (...)
Typically the low side is PWM and it's output feeds a (+) charge pump diode cap, for the high side gate driver in IC's using Pch high side FET's
I have a question which I don't know is valid or not. In a charge pump PLL, the D flip flop based phase Frequency Detector (after reference and divided frequency outputs get locked in phase and frequency) generate periodic spikes in the UP and DOWN outputs. These outputs are applied to the (...)
You need to define certain parameters first, like type of PLL - integer or fractional, then reference frequency, frequency divider ratio, KVCO of the VCO, the charge pump charging or discharging current, maybe loop bandwidth and PLL phase margin, etc. After that you can go through the calculation of the values of loop filter (...)
I have question. If i make the phase locked loop of CDR(Clock and Data Recovery) which is composed of 2 charge pump circuit(Icp), i want maintain same bandwidth of CDR which is composed of 1 charge pump (I'cp) then, should i make currents of charge (...)
In CDR circuit, what is the most dominant factor contributed to jitter of clock? 1. charge pump current mismatch. => phase Detector UP/DN signal is not wide enough so charge pump can not switch properly. 2. Ripples of VCO control voltage. => (...)
108926 in the above circuit there are NMOS and PMOS Current mirror circuits. PMOS SW and NMOS SW blocks represent the mos switches. the W/L ratio for Current mirror circuit is 10/0.18um. the W/L ratio for switches are 2.3/0.18. If the w/l ratio is increased then the output current provided by the current mirror circuit i
hi, i am having a pll operating at the range 1-500 Mhz. I have designed pmos and nmos switches but the output of the switches is wrong. can anyone help me about which parameter should i change in the pmos and nmos switches so that i get right output. is it the w/l ratio? or anyother parameter
106959 this is a phase frequency detector. can i find the dead zone of this circuit without charge pump. if yes then guide me how to find the dead zone of this circuit.
The charge pump converts the logic states of the detector into analog signals appropriate for controlling the VCO. The mixer is a current mirror with duty cycle control so it emulates an integrator with a gain factor K1/s . The phase detector has boundaries, within those are linear but outside at harmonics is recursive, so (...)
two basic stages. the first is to buy/build an inverter to convert the variable voltage output to charge a battery. The second is to buy/build an inverter to convert the DC battery voltage to a suitable 3 phase AC supply for your pump. You will need a large battery, as your motor uses 5 X .75 KW ~ 3.8 KW, the inverter will (...)
hi crutschow, i am working on the same thing. mine can be both analog and digital. the block diagram consist of local oscillator, PFD, charge pump, filter and VCO. the output frequency is targeted at 1000MHz. I intend to use CE colpitts oscillator to realise the VCO. please i need help. your help will be appreciated.
Good Day, Presently, I am designing a charge pump for usage in PLL. But had encountered some challenges. The Vout constantly increases regardless of the Up or Down pulse width variation. My understanding was that with Up pulse wider than Down pulse, Vout would increase. Down pulse wider than Up pulse, Vout would decrease and when both is equ
Hi, Actually you have to fix the BW, phase margine that you expects for your PLL. Ones this done you can calculate the required current for charge and discharge. By knowing the process parameter K, Vth, .. you can easily determine the dimension of your transistor using the Ids equation.
I wanted to start designing some polar feedback systems using a PLL for phase correction, but I really want to avoid using a digitally programmable PLL. I'm able to use microcontrollers and such, but I really don't want to put one on a PCB for the soul purpose of programming a PLL once on power up. So I was hoping to basically find a chip with a
I would like to know why fractional spurs are more of a problem in All digital PLL when compared to more traditional charge pump PLLs. I'm guessing it must be because of the sampling nature of the TDC . Are the fractional spurs that fall beyond the reference frequency folded back due to aliasing? Any references with detailed analysis of this or exp
Hi, I am converting a single charge pump PLL having loop element as R, Cbig, Csmall and CP current as Icp, into dual charge pump PLL having loop element R(=1/gm, unity gain buffer o/p impedence), Cbig/2, Csmall/2 and proportional and integral charge pump current as Icp and Icp/2. As per (...)
It is strange for the VCO to get a single freqency with 4.3/4.7V vtune. One case should be unlocked. You can try to tune the charge pump current register to observe and optimize the phase noise. ADF4157 has best performance when VTUner is btween 0.5V and Vp-0.5V. The Vp should be clean.
An internal charge pump with a cap is equivalent to an external integrator with a reference voltage equal to no phase error. When the phase error is a pulse controlled current source going into capacitive load , they call it a charge pump or essentially an (...)
Hi This is rizwan.I am designing a charge pump in which i need 4 clock pulses.can anybody of you have idea of splitting 4 phase from a clock generator.Pls reply urgent.