CDCVF2310: Clock buffer to replicate SDI signal

Francesco Bernardini

Part Number: CDCVF2310
Other Parts Discussed in Thread: LMK00101

Tool/software:

Good afternoon,

For a project where a MC drives 10 other chips using the SPI protocol, I am using a CDCVF2310 to replicate the SCK signal before I pass it to the devices.

I was wondering if I could use another CDCVF2310 to duplicate also the SDI signal, even though it's not a clock.

Naively I would say yes, as it's a signal just like the clock (only less regular), which at most can vary at half the clock frequency. But maybe I am overlooking something else, and I'm quite new to the field, so I would like to double-check with yall.

https://www.ti.com/lit/ds/symlink/cdcvf2310.pdf

Thank you in advance!

Francesco

5 months ago

0 vicente flores prado 5 months ago

TI__Mastermind 23791 points

Hi Franceso,
What is the SDI Clk frequency, swing, and common mode voltage?

Best regards,

Vicente

0 Francesco Bernardini 5 months ago in reply to vicente flores prado

Prodigy 10 points

Hi Vicente, the MC I am using has a 16MHz crystal, so if I'm correct the SPI frequency would be 8MHz at most;

The same MC is powered at 3V3

0 vicente flores prado 5 months ago in reply to Francesco Bernardini

TI__Mastermind 23791 points

Hi Franceso,
So, the clock signal is just a 3.3V 16MHz SE signal? Is this LVCMOS?

I just want to ensure I understand what kind of signal you wish to buffer.
What

0 Francesco Bernardini 5 months ago in reply to vicente flores prado

Prodigy 10 points

Yes, the clock is 3.3V single ended, the maximum frequency I can reach with that microcontroller is at most 18MHz;

The technology I would imagine to be CMOS given it's an ARM microcontroller from ST, however the datasheet says that each port is CMOS and TTL compatible

+1 vicente flores prado 5 months ago in reply to Francesco Bernardini

TI__Mastermind 23791 points

If it's 3.3V LVCMOS & you need 10 copies of this then LMK00101 is a good option.

Best regards,

Vicente

0 Francesco Bernardini 5 months ago in reply to vicente flores prado

Prodigy 10 points

Good evening Vicente, thanks a lot for your answer;

Just for my understanding, what feature in particular makes the LMK00101 preferable to the CDCVF2310?

I see from the datasheet both are 3.3V and LVCMOS compatible, and they have similar prices;

maybe the LMK00101 is newer, or has better performances overall?

Thanks again!

0 vicente flores prado 5 months ago in reply to Francesco Bernardini

TI__Mastermind 23791 points

That & the universal input.
Otherwise CSCVF2310 works just as fine.

Best Regards,

Vicente

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CDCVF2310: Clock buffer to replicate SDI signal