Question

Problem-2 [150] In the figure shown below, the transistor T, is used as a switch for the load resistance R₁. The circuit data are the following: the voltage of the main

de source,Vcc= 200.006/V/; the voltage of the base de source, V₁= 3.5 /V/; the load resistance, R₁= 1.98006 /2/; and the resistance of the base circuit, RB = 0.0625 /22/. V₂ RB is BE ic (6) ACE Re + Vcc 1/nComments: The values shown for the main de voltage source and the load resistance do not look too realistic. The reason is to have the data of the shown circuit in agreement with the waveforms that follow. The switch is shown on the base circuit to model the control process that is present on the base circuit. For a cycle of the transistor operation, the waveforms for different quantities are shown in the attached Figure 8-10. The length of different time intervals shown in the figure is as follows: ta = 0.5 /μs/; t₁= 1 /µs/; ts = 5 /µs/; tf = 3 /us/. It is also specified that the signal frequency is fs= 10 /kHz/ and that the duty cycle is D = 50% (Here the duty cycle is defined as the ratio of the time length along which the base signal is present to the total time length of a cycle. With the data shown in Figure 8-10, the duty cycle is represented as: D /%/= ((ton+ tn)/T) x 100)./n200/vl 2/V] =VCE(sat) 1001A=Ics 3/MA/= ICEO ·0 8/A/= ¹8s -3/V/ = V₁E(San counted as t=0 karte & H. ig 1 VBE tn 1 +-+-+- •T = 1/₂ to Figure 8-10 Waveforms of transient switch./nFor the given circuit and its operation, calculate the value of: a) The energy consumed (lost) within the transistor, due to the collector current during the initial turn-on time-interval, that is, for 0 ≤t≤ta. b) The same quantity as in a) during the final turn-on time-interval, that is, for ta ≤ t ≤ton. c) The same quantity as in a) during the full conduction time-interval, that is, for ton ≤ t ≤ (ton + tn + ts). d) The same quantity as in a) during the initial turn-off time-interval, that is, for (ton + tn + ts) ≤t≤ (ton + tn + toff). e) The same quantity as on a) during the full turn-off time interval, that is, for (ton + tn + toff) ≤ t ≤ T. f) The total energy and the corresponding average power consumed (lost) within the transistor along an operation cycle, due to the collector current. g) The energy and the corresponding average power supplied by the base voltage source VB along an operating cycle. These correspond to the energy and the average power consumed (lost) within the transistor and in the base circuit resistance, R₁. h) The total energy and the corresponding average power consumed (lost) per transistor, that is, due by both the collector and the base current, including the energy and the corresponding average power lost in the base circuit resistance Rb./nj) i) For one cycle, the total energy and the corresponding average power supplied to the circuit by the main voltage source, Vcc and by the base voltage source VB. For one cycle calculate the total energy and the corresponding average power consumed by the load resistance R₁. For this purpose, you must use the load resistance R₁'s value and the corresponding collector current. k) Calculate the following difference: (total energy defined in (i)) minus (total energy defined in (h)). The same difference can be defined by using the corresponding average powers. Compare the difference obtained here with the values obtained in (j). 1) The circuit efficiency in percent, counting the total energy or the corresponding average power supplied by both, the main and the base de source, and the total energy or the corresponding average power lost in the transistor and in the base power resistance Rp. For the same purpose, it can be counted the total energy or the corresponding average power supplied by the main and base de sources and the total energy or the corresponding average power absorbed by the load resistance R₁. m) Along an operation cycle, plot the instantaneous power carried by the transistor, counting only the collector current. On the graph clearly specify the value for the maximum and minimum value of the instaneous power and the corresponding moment in time when each of these is reached.

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