CDCV304: CDCV304 output duty cycle

Bruce Llin

Part Number: CDCV304
Other Parts Discussed in Thread: CDCVF2505,

Hi TI Expert,

In our design, CDCV304PW had be used for fan-out four 25MHz clock to CPU/CPLD/FPGA/PHY, we found 25MHz output duty cycle is 44.692%~45.150%, which not meet our applycation (45%~55%),

Anymore, the 25MHz intput duty cycle is about 50%, do you have any better suggestion how to promote the duty cycle?

I also attached my schematic and test waveform for your checking, thanks!

Best Regards,

Bruce

over 4 years ago

0 Lane Boyd over 4 years ago

TI__Genius 16845 points

Hi Bruce,

I checked the schematic, it looks OK. Do all outputs have the same duty cycle?

Have you tried adjusting R289? It is possible the value will have some impact on duty cycle.

CDCVF2505 is a device with compatible pinout and can provide the desired functionality. Consider CDCVF2505 if 50% output duty cycle is a critical requirement.

Kind regards,
Lane

0 Bruce Llin over 4 years ago in reply to Lane Boyd

Prodigy 140 points

Hi Lane,

thanks for your great support, we will try to adjust R289,

one more question, i didn't find any duty cycle parameter on CDCV304 datashee, can you show them for me?

How about the cost between CDCV304 and CDCVF2505, can you help provide some CDCVF2505 sampels for me, thanks!

Best regards,

bruce

0 Lane Boyd over 4 years ago in reply to Bruce Llin

TI__Genius 16845 points

Hi Bruce,

There is no duty cycle spec in the CDCV304 datasheet.

The cost appears to be similar for either device. The sample request process recently changed here at TI. To request samples, follow the instructions at this link: www.ti.com/.../sample-request.html

Kind regards,
Lane

0 Bruce Llin over 4 years ago in reply to Lane Boyd

Prodigy 140 points

Hi Lane,

thanks for your reply, which help me a lot!

Best regards,

Bruce

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CDCV304: CDCV304 output duty cycle