TDA3: clkout jitter

ytakano

Part Number: TDA3

Hello,

TDA3x has clkout[2:1] which can be used as a system clock for other devices.

A customer would like to use the clkout pin to be fed to DS90UB964:REFCLK input which is required jitter 100 ppm as shown below DM of UB964.

Can clkout pins of TDA3x be applied to DS90UB964:REFCLK?

Regards,
Yoshi Takano

over 9 years ago

0 Dian Iliev over 9 years ago

TI__Intellectual 1245 points

Hi Yoshi-san

This should be a valid option!
However, please note that in this case you should use source with the required characteristics.
i.e. if you use OSC1 as a source signal, Frequency accuracy characteristics of the crystal should be within the required range (accounting for tolerance+stability+aging.)

Best Regards,
Dian

0 Rajesh Veettil36 over 9 years ago

TI__Prodigy 420 points

Takano-san,

It is possible but a lot of things to consider... What is the frequency of crystal connected to the OSC0/OSC1 interfaces of TDA3?

And what is the frequency /jitter specification of those crystals? That will matter as the UB964 Frequency/Jitter tolerance is tighter than what is specified for TDA3X.

Also I request you to refer to the TDA3 TRM to see what internal clocks can be brought out on the CLKOUTn pins.

Best Regards,
Rajesh Veettil

0 Dian Iliev over 9 years ago in reply to Rajesh Veettil36

TI__Intellectual 1245 points

In addition, note that OSC0 can not be used as a direct source in this case!
Available options for OSC0 are 19.2, 20 and 27, while DS90UB964:REFCLK requires 25 MHz or 23 MHz.

Thanks,
Dian

0 ytakano over 8 years ago in reply to Dian Iliev

TI__Genius 9095 points

Thanks for the reply.

Regards,
Yoshi Takano

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TDA3: clkout jitter