RTC - faking the external XTAL

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cadi_1014291
Level 6
Level 6
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Hi.

   

Another n00b question to my collection, i was trying to make the RTC work on the 5LP prototyping kit, external 32.768 KHz XTAL is needed.

   

Is it possible to generate that clock inside the PSoC, connect it to a pin, connect that pin externally to the XTAL input pins, and fake it?

   

Already create 32KHz clock and output it on a pin, i got 31.98KHz signal, see atached to see the idea.

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ETRO_SSN583
Level 9
Level 9
250 likes received 100 sign-ins 5 likes given

The 32 Khz onboard oscillator has special bias conditions that make it

   

a non CMOS compatible input if I am not mistaken. So consider filing a

   

CASE and asking that, as well as can you AC couple to the xtal input side

   

pin an external 32 Khz source, that might work. Post the answer back here

   

for the benefit of the forum.

   

 

   

To create a technical or issue case at Cypress -

   

 

   

www.cypress.com

   

“Support”

   

“Technical Support”

   

“Create a Case”

   

 

   

You have to be registered on Cypress web site first.

   

 

   

Regards, Dana.

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