jitter amplification

transient noise and rms_jitter function

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RJ(rms): single Edge or Both Edge?

RJ(seed): what is it?

phase noise method

Directly compare the input phase noise and output phase noise, the input waveform maybe is the PLL output or other clock distribution end point

Jitter Impulse Response(JIR) & Jitter Impulse Response(JIR)

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Example

Low Pass Filter

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N = 32;
x = zeros(N,1);
x(1) = 6;
x(2) = -2;
x(3) = 0.5;
x = x/5;
figure(1)
stem(x)
Y = fft(x, N);
figure(2)
plot(abs(Y(1:N/2)));

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High Pass Filter

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N = 128;
j_hp = zeros(N, 1);
j_hp(1)= 1;
j_hp(2) = 0.5;
j_hp(3) = -0.3;
j_hp(4) = 0.3;
j_hp(5) = -0.1;
jtf_hp = abs(fft(j_hp));
semilogx(jtf_hp(1:N/2+1));
xlabel('Freq');
ylabel('Jitter Amplification Factor');
grid on;

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inverter chain

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ji = 1e-12; % 1ps
data = importdata('/path/to/jir.csv');
jo = data.data(:, 2);
Ts = 31.25e-12;
Fs = 1/Ts;
jir = jo/ji;
N = 2^(nextpow2(length(jir)-1));
Y = fft(jir, N);
jtf = abs(Y(1:N/2+1));
freqs= Fs/N*(0:N/2);
plot(feqs/1e9, jtf, 'linewidth', 2);
grid on;
xlabel('Freq (GHz)');
ylabel('JTF');
title('JTF of inverter chain');

image-20220608233303576

Reference

Sam Palermo, ECEN 720, Lecture 13 - Forwarded Clock Deskew Circuits

B. Casper and F. O'Mahony, "Clocking Analysis, Implementation and Measurement Techniques for High-Speed Data Links—A Tutorial," in IEEE Transactions on Circuits and Systems I: Regular Papers, vol. 56, no. 1, pp. 17-39, Jan. 2009, doi: 10.1109/TCSI.2008.931647.

Phase-Locked Frequency Generation and Clocking : Architectures and Circuits for Modern Wireless and Wireline Systems by Woogeun Rhee (2020, Hardcover)

Mathuranathan Viswanathan, Digital Modulations using Matlab : Build Simulation Models from Scratch

Tony Chan Carusone, University of Toronto, Canada, 2022 CICC Educational Sessions "Architectural Considerations in 100+ Gbps Wireline Transceivers"