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PaxInstruments / t400-electronics

Electronics for the Pax Instruments T400 temperature datalogger
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Suggestion: depopulate or remove external pullups on the buttons #189

Closed cibomahto closed 9 years ago

cibomahto commented 9 years ago

External pullups are usually only necessary when the traces from button to processor input are long, or expected to be subject to large amounts of external noise. Neither of these seems to apply here, and the internal resistors should work fine for the buttons.

screen shot 2015-08-15 at 2 46 51 pm

samchoy88 commented 9 years ago

I think these resistors keep in PCB layout but DNP in material list.

charlespax commented 9 years ago

Yes, Sam, let's keep them in the design as DNP. It can be useful to have them there in other derivative designs. For example, to make the LCD shield I just copied the Eagle files and removed a bunch of parts. It would be good to now have to add them back later. However, if we run into an issue we can solve by removing them, we should remove them. I made a note for production https://github.com/PaxInstruments/t400-electronics/issues/191