Transistor Series Voltage Regulator

Figure shows a collection that is regulator that is straightforward a transistor and Zener diode. The circuit is known as a show voltage regulator because the load passes which are present the show transistor Q1 as shown in Figure. The d.c that is unregulated. supply is offered towards the input terminals which means manufacturing that is managed obtained over the load. The Zener offers the guide diode voltage.

Operation. The voltage that is base of Q1 is held to a voltage that is fairly constant the Zener diode. For example, if 8V Zener (in other words., VZ = 8V) is employed, the beds base voltage of Q1 will remain more or less 8V.

1) In the big event that output voltage decreases, the increased base-emitter voltage causes transistor Q1 to therefore conduct more increasing the manufacturing voltage. The output voltage is maintained at constant level due to this.

2) If the production voltage increases, the paid off base-emitter voltage causes transistor Q1 to thus conduct less shrinking the production voltage. Consequently, the output voltage is maintained at a known level that is consistent is constant. The advantage that is main of circuit could be the comprehended proven fact that alterations in zener present are repaid with a element β. Therefore, the total outcome of zener impedance is considerably reduced and many other activities production that is stabilised obtained


1) Even though the alterations which are noticeable zener present are much reduced, yet the production is not definitely constant. It is because both VBE and VZ decrease using the upsurge in room heat.

2) The output voltage may not be changed efficiently as no means are such provided.