LMK00308: Have a doubt regarding termination on the clock input pins

Gerald

Part Number: LMK00308

Hi Experts,

Our customer has a doubt regarding what is the input termination on the clock inputs pins and what should be the trace impedance as he is driving these pins from a clock buffer which is generating a 85ohm HCSL output. So based on the input termination he has to select the trace impedance and the buffer clock out series termination but the datasheet does not mention about the clock input termination.

Please help advise. Thank you.

Best regards,
Gerald

over 1 year ago

+1 Asim Khan over 1 year ago

TI__Genius 9250 points

Hi Gerald,

Inputs of LMK00308 are high impedance. You would need external terminations for any source that you need at the inputs. I believe if its a HCSL then termination would be 50 ohm to ground.

Best,

Asim

0 Gerald over 1 year ago in reply to Asim Khan

TI__Genius 9580 points

Hi Asim,

They are using a buffer as an input source for LMK00308 which is generating an LPHCSL output. So what should be the input termination in that case?

Best regards,
Gerald

0 Asim Khan over 1 year ago in reply to Gerald

TI__Genius 9250 points

Hi Gerald,

If the input source is LP-HCSL to LMK00308 as you mentioned. Then we don't need any terminations.

Best,

Asim

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LMK00308: Have a doubt regarding termination on the clock input pins