Pnp Transistor High Side Switch

Figure 8 2 shows a circuit using a pnp transistor as a high side switch.

Pnp transistor high side switch.

Some of the applications use a power transistor as switching device at that time it may necessary to use another signal level transistor to drive the high power transistor. The opposite of the low side switch is the high side switch. Transistor as switch. We ll need a more complex circuit to implement a practical high side power on switch.

Which means that pnp transistor shown in the first image will always be on regardless of the i o pin state. Transistor is 3 terminal electronic semiconductor component device. Higher base currents will damage a bjt. I normally would switch the high side second diagram but i guess the first method should also work although it would dissipate more power in the transistor and not have.

Both npn and pnp transistors can be used as switches. This time however the emitter is tied high. Using pnp transistors is essentially the same as npn transistors except the polarities are reversed. Based on the voltage applied at the base terminal of a transistor switching operation is.

It has three terminals named as base emitter and collector. The circuit above is called a low side switch because the switch our transistor is on the low ground side of the circuit. The arrow in the emitter of a pnp transistor points in the opposite direction than in an npn transistor. I saw a suggestion on using a pnp for switching a load on the low side with the collector grounded emitter following the input first diagram as opposed to the high side.

Transistor name meaning lies in its own working. This transistor connects between v and the load. Because of how transistors work these can be a little more difficult to use in an arduino or raspberry pi circuit. When npn turns on it sinks current through r1 r2 and this creates a voltage drop to the base of pnp which turns it on.

Similar to the npn circuit the base is our input and the emitter is tied to a constant voltage. Typically these use a pnp bjt or p channel mosfet. The first important thing to bear in mind to use a current limiting resistor at base. The real switch is still the pnp transistor on the right.

Notice that the emitter is connected to the positive voltage. Npn transistor as a switch. To explain with a pspice model pn2907a transistor has been selected. Trans istor transistor the prefix trans tells about signal transfer from low resistance to high resistance part and istor means solid physical structure having property of resistance.

The application of an pnp transistor is to work as a high side switch.