LMK04800 datasheet(21/79 Pages) NSC

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E V A L U A T I O N

B O A R D

O P E R A T I N G

I N S T R U C T I O N S

Recommended Test Equipment

Power Supply

The Power Supply should be a low noise power supply, particularly when the devices on the

board are being directly powered (onboard LDO regulators bypassed).

Phase Noise / Spectrum Analyzer

To measure phase noise and RMS jitter, an Agilent E5052 Signal Source Analyzer is

recommended. An Agilent E4445A PSA Spectrum Analyzer with the Phase Noise option is also

usable although the architecture of the E5052 is superior for phase noise measurements. At

frequencies less than 100 MHz the local oscillator noise of the E4445A is too high and

measurements will reflect the E4445A‟s internal local oscillator performance, not the device

under test.

Oscilloscope

To measure the output clocks for AC performance, such as rise time or fall time, propagation

delay, or skew, it is suggested to use a real-time oscilloscope with at least 1 GHz analog input

bandwidth (2.5+ GHz recommended) with 50 ohm inputs and 10+ Gsps sample rate. To

evaluate clock synchronization or phase alignment between multiple clock outputs, it‟s

recommended to use phase-matched, 50-ohm cables to minimize external sources of skew or

other errors/distortion that may be introduced if using oscilloscope probes.

LMK04800 Datasheet(PDF) 21 Page - National Semiconductor (TI)