PSoC5 GPIO Max Output Capacitance

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Anonymous
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I have been using the PSoC5 for some CNC motion control applications.  I was using the CY8CKIT-059 and was having trouble with some pins not working for stepper motor step generation.    When looking at the schematic I saw that P0_2, P0_3,P0_4, and P3_2 have 1.0uF capacitors. See the attached schematic snippet.

   

I think those capacitors are killing my short (a few usecs) step pulses.  I will probably remove the caps.  I was wondering how much capacitance the I/O can handle before it is damaged.  I could not find the spec in the datasheet.

   

BTW: If you are interested in CNC motion control on PSoC see my blog post.

   

http://www.buildlog.net/blog/2017/02/psoc-5-port-of-the-grbl-1-1-cnc-controller/ 

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Bob_Marlowe
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The caps on the pins you mention have some sense. They stabilize Vref and support the capsense components with the required Cs. I would suggest you to choose some other pins for your CNC interface.

   

 

   

Bob

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