Circuit to Measure Phase Noise of SN54LS628?

Cheri Anaclerio

Other Parts Discussed in Thread: SN54LS628

What do I need to put on the output of the SN54LS628 VCO chip to measure its phase noise with a spectrum analyzer (50 Ohm load)?

Thank you

0 Cheri Anaclerio over 8 years ago

I will use a TTL driver at the output. When I don't, it seems that a 50 Ohm load causes the part to become unstable.

0 Arvind Sridhar over 8 years ago in reply to Cheri Anaclerio

Hi Cheri,

Have you tried using an AC coupling capacitor between the VCO output and 50 ohm load?

Regards

Arvind Sridhar

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