Pull-Down resistors - correct usage?
Morrolan
Posts: 98
Hi guys - I know the principles of pull-up and pull-down resistors now thanks to you guys, but I just want to check one final time that I am using them correctly.
Sorry for the messy looking schematic, it's part of a much larger schematic where space is limited on my sheet.
CON and EXT are connector headers which both lead to a switch. The device is battery powered to the pins are pulled to ground normally and go "active-high" when pressed. Reset I believe is tied high internally (this is a BS2e at the moment, moving to a BS2p soon hopefully for power reasons).
Is this circuit correct if R1 and R2 are 10K?
Many Thanks,
Morrolan
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Flying is simple. You just throw yourself at the ground and miss.
"I think computer viruses should count as life. I think it says something about human nature that the only form of life we have created so far is purely destructive. We've created life in our own image."
Stephen Hawking
Post Edited (Morrolan) : 10/17/2007 12:49:52 PM GMT
Sorry for the messy looking schematic, it's part of a much larger schematic where space is limited on my sheet.
CON and EXT are connector headers which both lead to a switch. The device is battery powered to the pins are pulled to ground normally and go "active-high" when pressed. Reset I believe is tied high internally (this is a BS2e at the moment, moving to a BS2p soon hopefully for power reasons).
Is this circuit correct if R1 and R2 are 10K?
Many Thanks,
Morrolan
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Flying is simple. You just throw yourself at the ground and miss.
"I think computer viruses should count as life. I think it says something about human nature that the only form of life we have created so far is purely destructive. We've created life in our own image."
Stephen Hawking
Post Edited (Morrolan) : 10/17/2007 12:49:52 PM GMT
676 x 348 - 24K
Comments
It is more common to use a pull-up resistor, because if something shorts out it usually shorts to ground. If your switch connected to Vdd shorts to ground it will cause a major problem.
If you use Vss and a pull-up resistor, if it shorts to ground it just looks like the switch is closed.
Bean.
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
My goal is to live forever...Or die trying.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
www.hittconsulting.com
·
Edit: Image attached
▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Flying is simple. You just throw yourself at the ground and miss.
"I think computer viruses should count as life. I think it says something about human nature that the only form of life we have created so far is purely destructive. We've created life in our own image."
Stephen Hawking
Post Edited (Morrolan) : 10/17/2007 3:37:52 PM GMT