Questions tagged [pll]
PLL is short for "Phase Locked Loop". A PLL is a circuit that is able to keep a local (voltage controlled) oscillator synchronized with an independent given signal frequency.
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Intermittent control signal injection clock sync
I have a big challenge in my design to overcome:
I need clock frequency accuracy of <0.2ppm with incredibly low power consumption.
What we are doing currently is, using a 3G transceiver' baseband ...
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Disadvantage of 3rd order vs 2nd order digital PLL with high C/N0?
I tried to determine the best choice between an aided 2nd order and an unaided 3rd order carrier digital PLL in a context where the \$C/N_0\$ is very high. From all aspects, the 3rd order loop seems ...
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What is wrong with my Simulink model of a first order Delta Sigma Modulator?
I'm trying to design a Delta-Sigma Modulator for frequency synthesizer applications and am (just right now) figuring out how to properly configure a first order DSM in Simulink. I've made a few small ...
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Phase Locked Loop Frequency Multiplier x 100
Can someone please help me with selecting resistors and caps.
I have a PLL set up using a CD4046BE (PC2) connected to 2 x CD4017 decade counters to enable a x100 multiplier.
My input frequency range ...
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Can I use a PLL to generate the *phase* component of an SSB signal?
I want to use Kahn's method of Envelope Elimination and Restoration (EER) to produce a single-sideband, supressed-carrier (SSB) signal. Kahn simply clipped a low-level SSB signal, but I wonder if it ...
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Poor accuracy in PLL
I'm using the CDCE913 to output various frequencies in the range of 77.2-97.4 MHz.
When I program it to output a specific frequency using the calculations found in the datasheet, it doesn't output ...
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Low jitter clock multiplier
I am using a 2-channel arbitrary waveform generator to generate two 40 MHz signals. The AWG also has a trigger signal output: short (~20 ns) pulses of ~2.5 V. The AWG has a negligible jitter of about ...
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What Exactly Is Meant by a 2nd Order Phase Locked Loop?
I'm teaching myself about polyphase clock sync for demodulation of OQPSK. An article from gnuradio.org entitled "Polyphase Clock Sync" makes references to a 2nd order loop. The context seems ...
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Best way to close GPSDO PLL digital loop?
I am trying to build a GPSDO with a holdover capability of 500us/24hs (maximum drift accumulated).
The system uses a 10MHz OCXO and it is my intention to use a microcontroller (ATMega, STM or ...
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Problems Comparator II of this CD4046 for LTspice
I downloaded a CD4046B model from user ale_t, which can be found here:
https://www.electro-tech-online.com/threads/new-spice-model-for-cd4046b-phase-locked-loop-ic.149093/
However, the Phase ...
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How to interpolate phase noise curves?
I am trying to calculate the phase jitter of a transmitter. A phase noise profile is given, say:
...
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Design for a PLL Auto-Locking Circuit
I am looking into electrolysis efficiency using an auto-locking PLL circuit that is supposed to latch onto the resonant frequency of the electrolysis cell, a frequency determined by the inductance of ...
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How to make a PLL output the phase modulo 360°?
I have made a PLL to obtain the mechanical angle encoded in quadrature sine signals (the envelope of a resolver output) ; it implements: error=in-out is approximatively equal to sin(in-out)=sin(in)cos(...
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Matlab Phase Locked Loop Design : FM Demodulation
EDIT: It seems I've asked too much at once here. I'll do some more studying and come back if I have more specific questions.
I'm trying to design an analog phase locked loop in Matlab. I've read ...
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How to Create an FM Signal with a MHz Carrier Frequency and kHz Sinusoidal Information Signal for PLL in Simulink?
I am working on a project in Simulink that involves a Phase-Locked Loop (PLL). In this project, I need to use two different frequencies—one in the MHz range and the other in the kHz range. I am trying ...
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Type 2 comparator locking on ringing
I have successfully designed a 4046 IC with a phase 2 comparator locking to an external 10 MHz VCOCXO. The circuit is simple
vcoxco---->
divide by 10-->
Schmitt Trigger -->
divide by 10 -->...
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N-counter issue ADF4001
I designed and tested a PCB with a PLL circuit. The goal is to lock on the reference signal which is a square wave. The problem I am having is that the signal of the N-counter shows no response, just ...
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PLL Clock distribution
I am generating 40MHz clock using ADF4106 PLL Frequency Synthesizer with VCO CVCO55CL-0038-0042. I am using this 40MHz generated frequency for distribution using ADCLK846. Output power from PLL is -3....
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How does a PLL PFD produce a high frequency?
I am going to work with a PLL and a VCO.
I have read and understood the basic procedure in which the charge pump works. I understood that say, when the reference signal (or the divided signal) is up ...
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NE564 PLL chip operates on PCB only with loop filter pin 14 floating
This circuit has been implemented on my PCB. However, when I test this circuit (without the DRV135UA), it surprised me that the PLL works except Pin 14 of NE564D (V_PLL). At Pin 14, I did not measure ...
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Signal path / configuration help for a PLL for AWG
In our system signal path, there is a clock signal being sent from the FPGA noted as SCLK. This goes to each component not including the MCU.
The way I understand this is that the PLL receives the ...
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Why does the overshoot exist when transmitter turns on?
I am implementing power amp. with 16-QAM. Because of issue on power consumption, I am using time division duplex (TDD). By TDD, the power amp. turns off if the carrier wave is not needed and vice ...
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Approach to an unknown orthogonal Beta Signal with a known alfa in single phase dq transformation
I am trying to implement a PLL controller to the MCU for tracking single phase line voltage . I get samples via an opamp circuit with a DC offset and the samples' raw values vary between |-244 , +244| ...
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How to generate fast clock signal with MAX10 and PLL?
I'm using 10M50 FPGA to read data from a camera via MIPI-CSI2, but the clock I have on the board can't operate fast enough. So right now i'm trying to use the PLL to generate faster clock signal.
I'm ...
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Oscilloscope Phase Shift
I have a university research that i am conducting right now. My objective, as a first step, would be to phase shift an NRZ signal at high frequencies >40GHz, assuming this signal is already locked ...
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Can someone help me in getting to know what is wrong with my Frequency multiplier circuit using 565?
I just learned the working of NE565 and I tried to simulate a Frequency as multiplier using 565 in Proteus , but I don't know why PIN 4 of my NE565 is not giving any output . Its coming plane blank in ...
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Phase noise of a digital PLL
I assume the reader is aware of how a DPLL works.
The DPLL oscillates with a frequency of \$F_{out}\$.
The DCO free running frequency is \$F_{free}\$.
In the model of our DPLL we've only considered ...
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Common symbol for PLL
Is there a common symbol for PLLs, either for schematics or functional diagrams?
I need a symbol which would be easily recognized as a PLL, without having to draw the phase comparator, loop filter, ...
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PLL with two input frequency within lock range for FM demodulation
I have current output from a photodiode which I believe containing at least two distinct frequencies that is not too far apart from the lock range of a PLL which taking this current as the input ...
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Derivation of stability criterion for type 3 digital PLL
Could anyone help to derive the following expression (4.23) which is the stability criterion for type 3 digital PLL ?
Note: Screenshots are taken from Floyd Gardner's book : Phaselock Techniques 3rd ...
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PLL : conceptual confusion
In the PLL it is said that Capture range is the frequency from which the PLL starts functioning and Locked range is the frequency where the output of VCO is equal to that of reference oscillator ...
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Phase Locked Loop Gain Design- FM Demodulation
Say I am trying to demodulate a message up to 25kHz in frequency, with a peak frequency deviation of 75kHz and a carrier of 1MHz, implying a 200kHz bandwidth using carsons rule.
Would I design the ...
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closed loop zero in second order PLL with a proportional-integral filter
Why does the closed-loop zero in second-order PLL with a PI filter enhance the phase noise near PLL bandwidth frequency? I know that it enhances the phase margin but i can't find the logic behind why ...
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pragma directives to set frequency for dsPIC33
currently I set the frequency of my dsPIC33EV with following code:
...
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TDF transmitter to arduino
1) I have a project to build a time clock based on the TDF signal on 162kHz, from Allouis, France. The time coding is similar to DCF-77 so I will send it to an Arduino with proper code. I managed to ...
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HD-SDI monitor locks-unlocks
I have an SD/HD/3G-SDI output driven by a LMH0303, pretty much stock standard application circuit straight out of the datasheet.
The SDI datastream is generated by an XC7K70T FPGA, so I have great ...
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Digital PLL reference noise rejection
I have a fully digital implementation of a PLL.
The problem that I have is the white noise coming from the PFD (you can view it as input jitter). I would like to filter it a lot, but an implementation ...
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RF frequency synthesis - how low power can I reasonably go?
I'm an undergrad working on the analog frontend for a student-developed cube satellite. After looking at the options, I've decided to use the CML Microcircuits CMX994 for the receiver and the CMX998 ...
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Disciplining a TCXO from a broadcast reference source
In the UK (and much of europe), a broadcast time and frequency reference is available in the form of the MST radio time signal. This is broadcast using on-off keying on a frequency of 60 kilohertz, to ...
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Frequency locked loop for input jitter rejection
I have an application where I want to multiply from a xtal oscillator
at 32KHz to a system clock of 40MHz. A standard PLL isn't going to do the
job, because the 32KHz jitter is measured in ns. Since ...
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stm32f2xx HSI configuration does not work correctly
I'm using below settings (in SystemInit function) to configure a STM32F215RG MCU to work at maximum speed (120MHZ) with USB support:
...
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Doubt about Phase Locked Loop
How is it possible that the Signal Output will have the same frequencies as the Reference Signal?\$f_1\$, Frequency of the Reference Signal;\$f_2\$, Frequency of the VCO.
Let's assume that \$f_1>...
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PLL controls frequency or phase?
I have a slight confusion about the working of the PLL. I have been following this document about digital PLL. I want to use PLL to get the same frequency and phase as that of a grid for a grid ...
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Need Help Increasing PWM Frequency from 800 Hz to 8000+ Hz for DC Motor Speed Control
I'm currently developing a speed control system for a powerful 12V DC motor that pulls a heavy load. To enhance system efficiency, I need to raise the PWM frequency from the 800 Hz (PLC upper limit) ...
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Why the loop bandwidth must be much smaller than the input frequency to ensure settling behavior?
Razavi said, in Section 9.6 Loop bandwidth of his book RF Microelectronics that
In the design of PLLs, we impose... a loop bandwidth much smaller than the input frequency to ensure a well-behaved ...
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Transfer function of noise from Vtune of VCO to its output phase noise using VerilogA model
I am using the code below for VCO, and it is pretty standard and straightforward. I want to make sure that the noise transfer function from control voltage to phase noise is correct, as I am going to ...
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What options are there for multiplying clock pulses by non-harmonic values?
I have a MIDI clock signal which will output pulses at 24ppqn and a device I would like to synchronise which runs at 64ppqn. This is equivalent to a an ⁸⁄₃ clock multiplication.
My current method is ...
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Crystal load capacitor physical defect
I have a 16MHz crystal that is used to derive a 60MHz PLL.
I have not seen many issues but have a PCBA that loses its PLL lock. I'm not sure why but I looked at one of the load capacitors up close (...
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Delta Sigma Modulator for 2/3 Multi modulus divider used in FracN PLL
I have been trying to implement a Delta Sigma modulator for a 2/3 Multi Modulus divider. I am referring to Riley's paper: https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=229400
I have designed ...
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Generating sine, triangle (etc) waves from ttl output of a GPS module (Ublox)
I'm building a variable frequency standard using a Ublox gps board off Ebay. It'll be hooked up to an Arduino and you enter the desired frequency via a keypad. The signal from the module is a square ...