ICS9DB306 Datasheet, PDF (5/16 Pages) Integrated Circuit Systems – PCI Express, Jitter Attenuator

Integrated
Circuit
Systems, Inc.
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1k
TYPICAL PHASE NOISE AT 100MHZ
ICS9DB306
PCI EXPRESS,
JITTER ATTENUATOR
PCI Express™ Filter
100MHz
RMS Phase Jitter (Random)
1.5MHz to 22MHz = 3ps (typical)
Raw Phase Noise Data
Phase Noise Result by adding
PCI Express™ Filter to raw data
10k
100k
1M
10M
100M
OFFSET FREQUENCY (HZ)
The illustrated phase noise plot was taken using a low phase
noise signal generator, the noise floor of the signal generator is
less than that of the device under test.
Using this configuration allows one to see the true spectral pu-
rity or phase noise performance of the PLL in the device under
test. Due to the tracking ability of a PLL, it will track the input
signal up to its loop bandwidth. Therefore, if the input phase noise
is greater than that of the VCO, it will increase the output phase
noise performance of the device. It is recommended that the
phase noise performance of the input is verified in order to
achieve the above phase noise performance.
9DB306BL
www.icst.com/products/hiperclocks.html
5
REV. A APRIL 7, 2005