059 dev board question

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cross mob
Anonymous
Not applicable

I have 2 of these, now my question is with a 32.768 khz crystal

   

 

   

most of the crystals I can find on ebay have a load of 12.5pf, the board has 22pf caps.. will it work or what do I need to do.. I only need 2 crystals at most.. prolly just one cause I want to make a clock with it.

   

 

   

my other question is how best to be able to set the time? 

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4 Replies
Bob_Marlowe
Level 10
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I cannot find your mentioned 22pF caps in the schematic. As far as I see there are no populated Cs for the 32k x-tal.

   

 

   

Bob

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Anonymous
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        The caps are populated on my board. C41 and C42. Between PSoC5LP and P15_2/P15_3 on 'pins' connector. The specs for the Crystal that they spec in parts list (CFS308-32.768KDZF-UB) according to mouser and datasheet is 12.5pf. this part isn't available but similar ones (12pf) are. Whether these would work with 22pf caps is unknown by me. -Ed   
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ETRO_SSN583
Level 9
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This might help, and incorrect cap loading may or may not start up

   

osc, and certainly will result in a freq deviation from spec sheet.

   

 

   

http://www.cypress.com/?rID=37884     AN54439 - PSoC® 3 and PSoC 5LP External Crystal Oscillators

   

 

   

Regards, Dana.

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Bob_Marlowe
Level 10
Level 10
First like given 50 questions asked 10 questions asked

Me and my board were on Rev. 3, actual is Rev. 4 and there are the Cs populated and the xtal is shown in the schematic.

   

 

   

Bob

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