What is the difference in output between an NPN and a PNP transistor?
An NPN (also known as sinking) output is used when you connect a load between a power supply + and a sensor output terminal.
A PNP (also known as sourcing) output is used when you connect a load between a sensor output terminal and a power supply -.
A PNP (also known as sourcing) output is used when you connect a load between a sensor output terminal and a power supply -.