LMK00308: OSCin Pin

Pyungho Chung

Prodigy 30 points

Part Number: LMK00308

Tool/software:

Hello,

We are using lmk00308 in our design.

I have a question about the OSCin pin design.

1. When input selection is set to CLKin_SEL0, is there a problem with operation if OSCin is connected to GND?

2. When input selection is set to OSCin, is there a problem with operation if OSCin is connected to GND?

8 months ago

0 vicente flores prado 8 months ago

TI__Mastermind 29542 points

Hello Pyungho,
The state of CLKin_SELx determines input to the MUX.

Only if CLKIN_SEL1 is set to high will OSCin be the selected input.

If OSCIN is the currently selected input and OSCIN is grounded - nothing will happen as there is no input.

Best regards,

Vicente

0 Pyungho Chung 8 months ago in reply to vicente flores prado

Prodigy 30 points

I want to double check.

There is a bias inside. Is it okay if OSCin is connected to GND?

0 vicente flores prado 8 months ago in reply to Pyungho Chung

TI__Mastermind 29542 points

Hi Pyungho,
MY recommendation is to leave OSCIN float if unused.

Best regards,

Vicente

0 Pyungho Chung 8 months ago in reply to vicente flores prado

Prodigy 30 points

Sorry for bothering you.

When using OSCIN, what problems occur if OSCIN is connected to GND? As you said before, since there is no input, there seems to be no output, but I want to check if there are any other problems.

0 vicente flores prado 8 months ago in reply to Pyungho Chung

TI__Mastermind 29542 points

There will be no problem if you really want to GND this pin.
I would simply leave it float if not being used though.

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LMK00308: OSCin Pin