LMK00334 : termination circuit in case of using HCSL.

Kaka

Other Parts Discussed in Thread: CDCM9102, LMK00334

Hi TI Experts,

Please let me confirm the following question.

[Question]

AM572x EVM used the CDCM9102RHBR for PCIe as LVDS clock. My customer would like to use the HCSL clock type. So if change the clock device from LVDS to HCSL, how should we change the termination circuit?

If you have any question, please let me know.

Best regards

kaka

over 9 years ago

0 Arvind Sridhar over 9 years ago

TI__Mastermind 24205 points

Hi Kaka,

You can follow the schematic below to convert an LVPECL output from CDCM9102 into a HSCL input suitable for AM572x.

Regards

Arvind Sridhar

0 Kaka over 9 years ago in reply to Arvind Sridhar

Guru 24520 points

Hi Arvind,

Thank you for your response.
I knew the schematic. Is this described on the CDCM9102 datasheet?

I would like to know the case of using the LMK00334.

If you have any questions, please let me know.
Best regards.
Kaka

0 Arvind Sridhar over 9 years ago in reply to Kaka

TI__Mastermind 24205 points

Hi Kaka,

This termination schematic is not documented in the CDCM9102 datasheet.

LMK00334 is a HSCL buffer. The HSCL outputs just need an optional 33 ohms series resistor and a required 50 ohm shunt resistor to ground. The outputs can be DC coupled to the receiver.

Regards

Arvind Sridhar

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LMK00334 : termination circuit in case of using HCSL.