# CC Amp.pdf - 2 Common-Collector(CC Amplifier Ryerson...

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Last Updated: Jan. 1, 2017-AY 1 Ryerson University Department of Electrical & Computer Engineering ELE 404 Common-Collector (CC) Amplifier IntroductionIn this lab you will construct a Common-Collector (CC) BJT amplifier and acquaint yourself with its very important property, namely, buffering. This lab also provides you with an opportunity to analyze and test a multi-stage amplifier (a two-stage amplifier, to be exact). For this lab, you will need two 2N3904 NPN BJTs. Pre-lab AssignmentP1.Consider the CE amplifier of Figure 1, driving a load . Assume that , , , , , , and Also assume the capacitors to be short at the operating frequencies of interest. Then, manually calculate the DC (quiescent) currents and voltages of the amplifier, as well as the no-load voltage gain , voltage gain (with ), voltage gain (with and ), and output resistance , , . . Complete Table P1. Show all work. Figure 1. A Common-Emitter (CE) amplifier driving a load directly. Table P1. Quiescent and AC parameters of the CE amplifier of Figure 1. R1RCREVCCR2vEvBvOvCvIRSvS+-Signal SourceRLC1C3C2RE2CE AmplifierRoiC
Common-Collector Amplifier 2 P2.Now consider the two-stage amplifier of Figure 2, in which the CE amplifierof Figure 1not directly connected to the load, but it drives the load through a Common-Collector (CC) amplifier. Thus, the CC amplifier acts as a bufferbetween the CE amplifier and the load. That is, it makes the load appear much larger to the CE amplifier, to not bring down the output voltage of the CE amplifier, while its own voltage gain is close to (albeit smaller than) unity. Then, repeat the analysis of Step P1for the amplifier chain of Figure 2. Assume the same parameters as those you assumed in Step P1, with the addition that Complete Table P2. Show all the work. is . Figure 2. Common-Emitter (CE) amplifier of Figure 1 driving a buffered load. Table P2. Quiescent and AC parameters of the two-stage amplifier of Figure 2. R1RCREVCCR2vEvBvOvCvIRSvS+-Signal SourceRLC1C3C2RE2VCCRE3vE2CC Amp.(Buffer)CE AmplifierRoRi2iCiC2
Common-Collector Amplifier 3