LMK03033: Reference clock design

Michael Yang2

Part Number: LMK03033

I found a circuit problem recently, and the problem is that I feed a 10MHz refernce clock with 3 Vpp to LMK03033. The datasheef recommanded maximum value is 1.6Vpp. The function seems worked many years, but I sitll want to know if any side effect to this situation.

over 4 years ago

0 Lane Boyd over 4 years ago

TI__Genius 16845 points

Thanks for posting on E2E. I have assigned your post to the responsible engineer. He will respond to you soon.

Kind regards,
Lane

0 Michael Yang2 over 4 years ago in reply to Lane Boyd

Prodigy 20 points

Dear Lane,

The 3.3V CMOS 10MHz TCXO is directly AC coupled to OSCin pin of LMK03033C. The function seems be ok from -40 degree to 60 degree, but I want to know if it exist any potential threat.

It's an urgent issue. Plese help to reply it as soon as possible. Thanks!

0 Hao Z over 4 years ago in reply to Michael Yang2

TI__Mastermind 18070 points

Hi Michael,

I've seen cases where if the input amplitude is too high, the input detection fails and the PLL doesn't lock. Please note that we only characterize the device up to the datasheet limit. We are unsure of what happens beyond that limit. So we definitely recommend operating the device exactly as datasheet requires.

Regards,

Hao

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LMK03033: Reference clock design