CDCDB800: support 25MHz output

Chi Zhang2

Part Number: CDCDB800
Other Parts Discussed in Thread: LMK00338

Hi Expert,

my customer want to use CDCDB800 both for 25MHz and PCIe100MHz, but our datasheet, it only support 50M-250MHz.

so could you help to check why we couldn't support 25MHz, our P2P competitor could support 25MHz both(1-400MHz), here is 9ZXL08x1E datasheet

Chi

over 2 years ago

0 Evan Su over 2 years ago

TI__Mastermind 18950 points

Hi Chi,

We have paged a device expert, however it is not clear to me what information you want to find - do you want a technical explanation for why the minimum frequency of this part is 50 MHz?

Best,

Evan Su

0 Chi Zhang2 over 2 years ago

TI__Intellectual 2700 points

Hi Evan

I want to know could we support 25MHz output? If not, why, which spec will be worse?

Chi

0 Connor Lewis over 2 years ago in reply to Chi Zhang2

TI__Genius 12380 points

Hi Chi,

The CDCDB800 was designed and tested for PCIe 100 MHz use case. It will be functional at 25 MHz, but we haven't characterized the device at lower frequencies so we can't guarantee it's performance characteristics such as additive jitter, start up time, etc. Another option is to use LMK00338, which is another 8-output HCSL buffer that supports DC to 400 MHz.

Regards,

Connor

0 Chi Zhang2 over 2 years ago in reply to Connor Lewis

TI__Intellectual 2700 points

Hi Connor,

customer don't want to choose another TI solution, because our CDCDB800 competitor could support these 25MHz, so if we couldn't we will lose this opp totally, also customer will separate TI DB800 AVl code to other competitors' P2P solution, could you help to check with designer, what level will our addictive jitter and start up time in 25MHz? any expectation?

Chi

0 Connor Lewis over 2 years ago in reply to Chi Zhang2

TI__Genius 12380 points

Hi Chi,

I've moved this discussion to email, so I'll mark this thread as resolved.

Regards,

Connor

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CDCDB800: support 25MHz output