The transistor works like an electronic switch. It can turn a current ON and OFF. A simple way to think about it is to look at the transistor asa relaywithout any moving parts. A transistor is similar to a relay in the sense that you can use it to turn something ON and OFF. But a...
An ordinary NPN transistor will turn ON when the base voltage is about 0.65v more than the emitter but a MOSFET needs the gate terminal to be at least 2v to 5v, (depending on the type of MOSFET) above the source voltage. This is called theGATE VOLTAGEand the exact value is difficulty...
In the active region, the voltage applied to the emitter junction of the transistor is greater than the turn-on voltage of the PN junction. And the base current controls the collector current, so that the transistor acts as an amplifier, and its current amplification factor β=ΔIc/ΔIb. ...
Consequently, the transistor which may be conducting slightly more current through it might start getting heated up faster than the neighboring devices, and soon we may find the device entering into a thermal runaway situation damaging itself and subsequently transferring the phenomenon to the remaining...
How to Replace a Transistor (BJT) with a MOSFET In general we can easily replace a BJT with a MOSFET, provided we take care of the relevant polarities. For an NPN BJT, we may replace the BJT with a correctly specified MOSFET in the following manner: ...
If you want to learn more about how the transistor works and how to calculate the base resistor RB, you can check out our guide for using thetransistor as a switch. Automatic Street Light circuit with an LDR and Relay You might have noticed street lights that automatically turn on at night...
PNP transistor Switch A PNP transistor can be used in the same way as an NPN transistor. The difference is that in PNP, the load is always connected to the ground and the PNP will be used to switch power to the load. To turn the PNP transistor on, we must ground the base terminal ...
type layer
A TRANSISTOR AS A SWITCH Look atFigure 1. It shows a typical general-purpose (NPN) transistor/LED circuit. If you hook up +5 volts to Vcc in this circuit and pulse the input terminal (Vin) with +5V, 0V, +5V, etc., the LED will flash on and off accordingly. Of course, in orde...
One 7CT1N will test a PNP and while it is in place the second 7CT1N can be used to select a transistor that is closely matching as pair. There are two curves worth paying attention when comparing two complementary transistors. The first Step in the curve closer to zero should be ...