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[hjl4]

Can anyone refresh my memory? Back in college, we learned how to work with transistors, and used them as amplifier. My problem, is, how do you make the transistor act like a trigger, or let current through to the load when the base reaches a critical point?
For arguments sake, transistor opens the flood gates when base reaches 3 volts.
Is this possible or am I thinking of some other component??

Thanks for clearing this up.

 

[mcs51mc]

Check here: http://en.wikipedia.org/wiki/Schmitt_trigger
or here: http://hyperphysics.phy-astr.gsu.edu/hbase/electronic/schmitt.html