Suitable resistance value to hold pins to the ground

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rfsingh81@gmail.com
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Suitable resistance value to hold pins to the ground

Post by rfsingh81@gmail.com »

Hi
Could you please tell me some suitable resistance values to hold PIC12f635 pins to the ground. I would preffer to use the highest values possible as to prevent the current consumption when pin is externally made high by button press.
Thanks

medelec35
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Re: Suitable resistance value to hold pins to the ground

Post by medelec35 »

Since i/p pins have a high input resistance, hence all the warnings about static can damage...blah blah. I would say easily get away with 1 Meg or higher. If it were me I would go for 1 Meg. Then current drawn ignoring i/p resistance( cos it high as stated eailer :p) is 5/1X10E6=5x10E-6 = 5 microamps. Hows that for a low current?
If the other way round and you have a port B then you can enable weak pull-ups which are about 100K each, and have switch to pull down. That way you can eliminate the need for external resistors.
If I come across official resistances then I will update post.
Martin

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