Hello All,
I am working my way through the Book "Make Electronics" by O'Reilly.
In Chapter 4, page 156. The text indicates:
"R5 and R6 are known as "pull-up resistors" because they pull the voltage up.
You can easily overwhelm them by adding a direct connection to the negative side of the power supply"
Enclosed is the schematic being referred to.
My question is, As long as S1 and S2 are not pressed the voltage is up, almost to the power supply voltage, so why would you need the pull up resistors?
How do pull up resistors pull the voltage up?
Thanks
Joe
I am working my way through the Book "Make Electronics" by O'Reilly.
In Chapter 4, page 156. The text indicates:
"R5 and R6 are known as "pull-up resistors" because they pull the voltage up.
You can easily overwhelm them by adding a direct connection to the negative side of the power supply"
Enclosed is the schematic being referred to.
My question is, As long as S1 and S2 are not pressed the voltage is up, almost to the power supply voltage, so why would you need the pull up resistors?
How do pull up resistors pull the voltage up?
Thanks
Joe
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