I have been learning about transistors a lot lately. Following that I have managed to design a simple circuit that uses PNP transistor as a switch. Basically this is going to be a door alarm where if someone opens the door, alarm will sound. Reed switch will be the activator here which will interact with the magnet attached to the door.
SW1 is a reed switch here. Buzzer needs 30mA to operate
My question is do I need to add a resistor in series to the base of transistor in this circuit. I have observed almost in all transistor circuits that they add a resistor to limit the current flow.
If my understanding serves me right, in this circuit the emitter and base will be of same potential when reed switch is activated which will not allow any current to flow through the base terminal.
Did I got this right? Any advice is highly appreciated.