CDCE706: Minimum output frequency

Stefano Infante

Part Number: CDCE706
Other Parts Discussed in Thread: LMK01801, LMK05318

Hi all!

On my next design I wil use a CDCE706 with two clock inputs (2.048 and 16.384 MHz). I need a few 100 MHz outputs (no problem with those ones, I already tried them in an old design), but now I need a 400 Hz output as well. Is CDCE706 able to generate such a low frequency signal on a single output, while maintaining 100 MHz on others? If not, can you suggest a configuration/clock divider I could use?

Thanks in advance and best regards,

Stefano Infante

over 4 years ago

0 Adam Siismets over 4 years ago

TI__Intellectual 950 points

Hi Stefano,

That's a great question. Please give me a few business days to confirm details with the team and then I'll get back to you.

Regards,

Adam

0 Stefano Infante over 4 years ago in reply to Adam Siismets

Expert 2310 points

Hi Adam, any news about my issue?

Thanks

Stefano

0 Derek Payne over 4 years ago in reply to Stefano Infante

TI__Mastermind 31100 points

Hi Stefano,

The CDCE706 has 7-bit dividers, so the lowest frequency you could get out of CDCE706 by itself is several orders of magnitude higher than 400Hz. The LMK01801 buffer/divider has a set of outputs which can divide by up to 8360, so you could use CDCE706 to generate a lower frequency (e.g. 100MHz / 125 = 800kHz), then use the LMK01801 to divide by 2000 and generate the 400Hz output.

It might be more cost-effective to use a different IC capable of generating the required frequency without external components. As an example, you could use the LMK05318, which has an output with a 32-bit divider built-in.

Regards,

0 Stefano Infante over 4 years ago in reply to Derek Payne

Expert 2310 points

Hi Derek,

thanks for your reply. I will do some math and choose my best option.

Regards,

Stefano

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CDCE706: Minimum output frequency