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kflop's JP4 socket - short between VDD5 and Grnd pins?

Posted: Wed Oct 29, 2025 10:45 pm
by LakesideCNC
Hi,

While setting up my replacement Snapamp board for my mill, I discovered what appears to be a short between pins 1 (VDD5) and 8/9 (GRND) on the kflop's JP4 connector. For reference, I checked my other kflop board that I've been using on my lathe for many years and am seeing the same results when testing for continuity.

Is this common behavior for the kflop? Everything seems to be working okay from what I can tell but just want to make sure that everything is in order before I power up my new Snapamp board.

Thanks

EDIT: sorry, meant to say that it looks like 100 Ohms between the 5V and Grnd.

Re: kflop's JP4 socket - short between VDD5 and Grnd pins?

Posted: Thu Oct 30, 2025 4:01 pm
by TomKerekes
Well there is a lot of circuitry between 5V and GND so it is not surprising for an Ohm meter to measure some continuity.

Re: kflop's JP4 socket - short between VDD5 and Grnd pins?

Posted: Fri Oct 31, 2025 12:02 am
by LakesideCNC
Ok, that's what I thought but I wasn't seeing it between the 12v and ground pins so it made me concerned.

But, now that I think about it, I recall the manual mentioning that the 12v supply was a convenience for providing power to other devices and not actually required for driving the kflop circuitry so that explains why I'm not seeing it.

Well, sorry to waste your time but I appreciate the verification.

Re: kflop's JP4 socket - short between VDD5 and Grnd pins?

Posted: Fri Oct 31, 2025 12:14 am
by TomKerekes
But, now that I think about it, I recall the manual mentioning that the 12v supply was a convenience for providing power to other devices and not actually required for driving the kflop circuitry so that explains why I'm not seeing it.
Correct. 12V isn't connected to any KFLOP circuitry. It is only routed through to connectors for User convenience.

Well, sorry to waste your time but I appreciate the verification.
NP. better to be safe than sorry :)

Re: kflop's JP4 socket - short between VDD5 and Grnd pins?

Posted: Fri Oct 31, 2025 3:13 pm
by LakesideCNC
Thanks Tom!

Are the general purpose LVTTL pins (1-14) on the Snapamp's JP7 connector 5V tolerant or strictly limited to 3.3V only?

Re: kflop's JP4 socket - short between VDD5 and Grnd pins?

Posted: Fri Oct 31, 2025 3:49 pm
by TomKerekes
They are 3.3V LVTTL and 5V tolerant.

Re: kflop's JP4 socket - short between VDD5 and Grnd pins?

Posted: Sat Nov 01, 2025 12:50 pm
by LakesideCNC
Great, thanks for clarifying Tom!