LMK04832: clock generator input clock and VCXO requirements

Keshava Rajesh

Part Number: LMK04832

Hi,

We are planning to use LMK04832 clock generator in our application. Can you pl suggest input clock (crystal oscillator and VCXO) requirements ,that is jitter and ppm required for better performance.

regards

Keshava Rajesh

over 7 years ago

0 Noel Fung over 7 years ago

TI__Guru** 110850 points

Hi Keshava,

How are you going to use this device? Clock generation or jitter cleaner?

0 Keshava Rajesh over 7 years ago in reply to Noel Fung

Prodigy 150 points

Hi,
We want to use for both applications. Is it not possible? Can you pl clarify in EVM of LMK04832 clkin1 and oscin is used 122.88 MHz. Is there any specific reason to use that frequency.

regards
Keshava Rajesh

0 Noel Fung over 7 years ago in reply to Keshava Rajesh

TI__Guru** 110850 points

Hi Keshava,

122.88MHz is a typical clock frequency in CPRI system for use in telecom RRU equipment.
If you want clock generation, you can simply use PLL2.
If you want jitter cleaning, you will need both PLLs. Pick a VCXO having similar or better performance than the one we used in EVM will ensure you have good jitter at outputs.

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LMK04832: clock generator input clock and VCXO requirements