![]() ![]() ![]() We have learned about the three usefulīipolar transistor bias circuits which are the base bias circuit, the voltage divider bias, and theĬollector-feedback circuit. In this experiment we have learned many things. If the Vcc drops to +15 V the collector will drop with it as well. If RE is 470Ω instead of 47Ωthen the voltage across the collector will increase.ĭ. If the base is shorted to ground through a solder bridge then the collector voltage willīe zero because it is placed across a short.Ĭ. Transistor Biasing is the process of setting a transistors DC operating voltage or current conditions to the correct level so that any AC input signal can be amplified correctly by the transistor The steady state operation of a bipolar transistor depends a great deal on its base current, collector voltage, and collector current values. If R1 opens then the collector voltage will be equal to the Vcc which is +24V.ī. Choose bias resistors for voltage-divider bias that will provide reasonably stiff bias. It is desired to have the Q- Point set to approximately 20mA of collector current. 3 you need to bias the amplifier shown in Figure 7-6. Draw each of the three bias circuits tested in the experiment for the case of a pnp transistor. RC 2 kΩ 1 kΩ Construct the circuit below The voltage divider bias method demonstrated the least variation of the three configuration in comparison between the calculated results and measured values. VC 6 V 6 V 6 V 6 V By using falstad we verified our results :įor the next part of the experiment we built the following collector-feedback circuit:Īt first we measure and record the values of the resistors below : Here are the results for this part of the experiment: Table 4 :ĭC Parameter Computed Value Measured Value Q1 Measured Value Q2 Measured Value Q VB 1 V 2 V 2 V 2 VE 1 V 1 V 1 V 1 V For each transistor we measured VB, VE, IE, VRC, and VC and compared them to their calculated value to see if they are close. ![]() in this circuit we also used three transistors. We also computed the current across the emitter which is nearly equal to the current of the collector. We used each of the resistor and used them in the following voltage divider bias circuit: We calculated the voltage across the base, emitter, collector resistor, and collector. Here are the results for this part of the experiment: Table 2 : DC parameter Computed value Measured Value Q 1 Q 2 Q 3 VRB 11 V 11 V 11 V 11 V IB 11 μA IC 2 μA VRC 7 V 7 V 7 V 7 V VC 4 V 4 V 4 V 4 V for each transistor we measured VRB, VRC, and VC and compared each measured value with the calculated value to see if they are close. We used three different transistors within this circuit and recorded them as Q1, Q2, and Q3. We calculated the values for VRB, IB, IC, VRC, and VC. Three small signal npn transistors ( 2N3904 ) Measure and record the values of the resistors Table 1: Resistor Listed value Measured value RB 1 MΩ 0 MΩ RC 2 kΩ 1 kΩ For the next part of experiment we built the following circuit (shown in Figure 7-3): We used the 1Ω resistor as our base resistor, RB and we used the 2 kΩ resistor as our collector resistor, RC. Raymond Yap Date : 03-10- Table of ContentsĬonclusion Error! Bookmark not defined. Bipolar Transistor Biasing Name: Mahfuz Alam EMT-1255 – D452 laboratory. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |