Jitter is the deviation from true periodicity of a presumably periodic signal, often in relation to a reference clock. (From: Wikipedia)
Questions tagged [jitter]
61 questions
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How to add a controlled amount of jitter to a signal
Background
I am developing a digital clock and data recovery circuit and am now getting into the evaluation phase, focusing on testing the limits of the design and finding potential strengths and weaknesses. An important metric of this particular…
travisbartley
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Phase Noise(dBc/Hz) and Jitter
Jitter as wiki explains undesired deviation in the periodicity of the clock and Phase Noise is random fluctuation in the phase of waveform caused by jitter. Exploring deeper into these terms when I look at measuring units i.e. femtosec or nanosec…
AKR
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What causes jitter?
What are the hardware causes of jitter in a chip? Is it simply the clocks to blame, or maybe other components (such as transistors, capacitors, etc.)? Are the tracks bereft of fault?
Randomblue
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Sub microsecond jitter accuracy - what to use?
I have four TTL level signals that must change state in a particular order.
From the “go” signal on one of the lines, all toggling of the other lines will be done within 100 us. The other three signals will toggle at most a couple of times. The…
ignoramusextraordinaire
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Can phase noise be averaged out?
I have an ADC sampling a downconverted RF signal at fs. I obtain N=2^15 samples of the RF input signal "fcarrier + fs/10".
The more I average, the more the entire noise floor shifts down (as expected, 10dB/dec) but also the phase noise skirt. I can…
divB
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4
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A capacitor as loop filter of a DLL
I know that if a second order, type two PLL has only a capacitor as its loop filter, it is unstable because its phase margin would be zero. but why is it ok for a DLL to only have a capacitor as its loop filter and it doesn't need the resistor in…
Fateme
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Period Jitter vs. Phase Jitter
I've got an oscillator spec that states an RMS period jitter of 1.7 ps and an RMS phase jitter of 0.85 ps.
I know that period jitter describes the deviations from the oscillator's average period over a number of randomly selected cycles, I'm not…
geschema
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What are the jitter characteristics of PLLs internal to Stratix V FPGAs?
I am interested in knowing the deterministic and random jitter characteristics of PLLs internal to Stratix V FPGAs. I have looked through the Stratix V handbook but could not find numbers quantifying the jitter of their PLLs.
What are the jitter…
Randomblue
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3
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Clock jitter - ppm, ui, ps
I using Xilinx FPGA and need to use its PLL (MMCM or Clk Wizard)
I have on my board LVDS 200MHz clock with 50 ppm frequency jitter,
I took this and go to some converted I can find on the internet and I can see that 50 ppm from 200 MHz is a frequency…
Michael Rahav
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Jitter in 'ppm' and 'ns'
In many datasheets clock tolerance is in ppm and in some other it is in ns or ps. What is the difference in giving clock tolerance in ppm and ns/ps. How it can be converted from one unit to another?
Athuljith Ranjith
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How does retiming flip flop work?
I found the following circuit which acts as a "retiming flip flop". A similar version exists which uses the CLEAR (instead or PRESET input), data tied to VCC (instead of GND) and output taken from \$Q\$ (instead of \$\overline{Q}\$).
simulate this…
divB
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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:
+------------+-----------------+
| Offset (f) | L(f)_dB [dBc/Hz]|
+============+=================+
| 10 Hz | -58 …
rksat
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Microcontroller Power Transient Voltage Spike
First of all thanks for even taking your time to read this question. We are hoping someone can help assist us with an issue we have been having.
We are currently working on an automotive tail light design. The issue we seem to be facing is a simple…
jacob80
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STM32 Timer Discrete Jitter
I'm using a STM32F746 running at 200MHz. A timer (tim2) is counting up at 100MHz and triggers an update interrupt with the following simplified ISR that writes a pattern to GPIOB
void __attribute__((section(".itcm_text"))) TIM2_IRQHandler(){
…
1uk3
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Does dividing a clock increase its jitter?
I want to have my microcontroller and ADC using a clock derived from the same source in an effort to avoid intermodulation effects. All clocks are under 50 MHz.
The maximum SNR out of an ADC is bounded by the jitter of its sampling clock. This means…
sgdsgyhetwaraw
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