I am making a circuit that will have a 9v battery with the positive lead connected to a 7805 5v regulator. What transistor (npn) can I use that will act as an and gate ( what transistor will switch instead of amplify at 5v)? After that it is going to a four bit adder; if a charge were added to only the base, or only the collector, would a small charge be passed through that could trigger the adder.

I am confused how you can tell if transistor amplifies or switches at a certain voltage.

Does anyone know a transistor sold at electronic goldmine that would fit my needs.

If you find any transistor, could you tell me what resistor I would need for it (if at all) and link to it. If there are many that would work could you link to the cheapest one.
Any transistor can act as a switch or as an amplifier. "Yes but at different conditions, I want one that will act as a switch under my conditions."

What is driving the transistor? What does the regulator have to do with that? "The battery is driving both the collector and base (after switches) the regulator drops the battery down to five volts. I said 9v to 5v instead of 5v because 7805 might have an on board resistor, then you would know the voltage and amperage."

"fit my needs"? you need to tell us you need.
"A transistor that works as a switch at 5 volts, does not leak enough energy to trigger an adder, npn; hopefully is sold at electronics goldmine and cheap/small."

Please don't answer with questions justto get points.

Tagged with:

Filed under: Electronic Circuit Transistor

Like this post? Subscribe to my RSS feed and get loads more!