If you are designing your own intelligent “Graden Computer” with an optional digital plant moisture sensor/water pump controller that lights an LED to alert the user when it is time to water a potted ...

This simple circuit has helped me out on many occasions. It is able to check transistors, in the circuit, down to 40 ohms across the collector-base or base-emitter junctions. It can also check the ...

In the early days, PNP bipolar transistors were common, but the bulk of circuits you see today use NPN transistors. As [Aaron Danner] points out, many people think PNP transistors are “backward” but ...

Need to switch something on or off using a microcontroller? Using a transistor is one of the best ways to do this, but how exactly do you design properly for transistor switching? [Ben Krasnow] put ...

The transistor is probably the most important invention in electronic engineering and the basis for nearly all integrated circuits (ICs). The transistor is a three-terminal electronic device that can ...

Matching a sensor interface with a programmable logic converter or controller hardware that can accept only one type of input—npn or pnp—can be difficult. The last-stage modification circuit described ...