PNP means positive negative positive and viceversa. while both can be used on a circuit its polarity application must be followed.
diff. between npn and pnp transristor
NPN and PNP transistors function in essentially the same way. The power supply polarities are simply reversed for each type. The only major difference between the two types is that the NPN transistor has a higher frequency response than the PNP-because electron flow is faster than hole flow. Therefore high frequency applications will utilize NPN transistors.
NPN and PNP are transistor types. The difference in the way the layers of semiconductor material are doped with impurities.
pnp answer
pnp and npn transistor
There is no difference they perform the same functions.
NPN, PNP only classified to BJT, while FET classified as P-channel , N-channel
BT169 is neither an NPN nor a PNP transistor. BT169 is a thyristor, otherwise known as a silicon controlled rectifier.
pnp
Switching is faster in NPN transistor than PNP. Because movement of electrons is faster than holes.
npn is preferred to pnp since n-doping can be pushed to higher values without damaging silicon lattice. due to this fact, doped regions can be less resistive. difference between npn and pnp is becoming smaller and smaller, tho.
PNP is sourcing. NPN is sinking. You generally connect NPN to ground and your PLC(or any load)input. With PNP you connect to V+ and to your PLC. Your PLC (load) should have the same ground or V+. Sourcing (PNP) provides a path to +24DC generally. Sinking (NPN) provides a path to 0V DC.