Wednesday, March 9, 2016

Difference between PNP and NPN sensor

In industrial control applications, there are many types of sensors that are used as photo switches, proximity switches and others. All sensors it uses three cable terminals, two terminals are used as the supply voltage is usually marked by a brown color to VCC + and blue for VCC -. One terminal is again used for signal output which is usually marked with black.

This type of sensor is a sensor type of transistor. This is coupled with the output drive transistor. Of the transistor circuits, sensors are divided into two types of sourcing or sinking or PNP and NPN. Have you known about the difference between PNP and NPN sensor ? To know the difference between PNP and NPN sensor, you can read the discussion as follows.

difference between pnp and npn sensor

Definition of PNP and NPN sensor

PNP sourcing sensors or a combination of detector and output circuits are made of PNP transistor types. When the conditions are normal and no object is detected, the transistor will be lit (ON). This cause there is current flowing from the emitter toward the sensor output to the load. This is what causes the sensor called the current source or commonly called sourcing sensors.

In simple applications, the sensor output can be used to drive the load that has been linked to the flow negative. It aims to consider the current handed over to avoid excessive load so that it can prevent the sensor from damage.

Sinking NPN or PNP sensor is the opposite of or sourcing sensors. On the call with NPN since this sensor is a type of sensor made of a combination between the detector and the output that was created from an NPN transistor.

The working principle of PNP and NPN transistor

Difference between PNP and NPN sensor just not about the definition, but also the principal working. Difference between PNP and NPN sensor on principal workings of both these sensors would have been different. The first is the working principle of sensors NPN, NPN current work in the system will flow from the collector to the emitter when the base is connected to the negative or ground. In this case, the current that flows from the base to be smaller than the current flowing from the collector to the emitter, so it should fit either a resistor pin basis.

While the second working principle is the working principle of the sensor PNP. System sensors work are current will flow from the emitter to the collector current to the base pin is supplied with a voltage source. Just as the NPN sensors, the current flowing into the base must be smaller than the current flowing from the collector emitter. With so then the pin base resistor must be installed.

That is information about the difference between PNP and NPN sensor. Both of these sensors have a working principle and the different uses that you should know before applying.


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