So, a crucial thing to note is that you have to know the direction of the current flow. In general, NPN and PNP are the terms for the type of output transistor used in a sensor to switch the load. The ...

A versatile signal-conditioning circuit for use with with programmable logic converters or controllers that can accept only one input polarity. Matching a sensor interface with a programmable ...

In the early days, PNP ... a transistor and you’ll see it isn’t much different from an NPN except the base-emitter diode junction is reversed. As you might expect, current has to flow through ...

In an NPN transistor, a positive voltage is given to the collector terminal to produce a current flow from the collector to the emitter. In a PNP transistor, a positive voltage is given to the ...

of a heated sensor as shown in the empirical thermal impedance formula below. It quantitatively relates junction temperature rise, power dissipation, and air flow speed for a self-heated 2N4401 ...