Q35 of 40 Page 93

Assuming the ideal diode, draw the output waveform for the circuit given in Fig. 14.17. Explain the waveform.


The diode remains in forward bias till 20sinωt>5v. so, the circuit becomes,



Hence, we get a constant supply at the output. V0=5V


As soon as 20sinωt < 5v happens, the diode goes into reverse bias state. So, the circuit becomes,



Hence we get the same output as per the input.



The waveforms look like



More from this chapter

All 40 →
33

Draw the output signals C1 and C2 in the given combination of gates (Fig. 14.15).


 34

Consider the circuit arrangement shown in Fig 14.16 (a) for studying input and output characteristics of n-p-n transistor in CE configuration.


Select the values of RB and RC for a transistor whose VBE = 0.7 V, so that the transistor is operating at point Q as shown in the characteristics shown in Fig. 14.16 (b).



Given that the input impedance of the transistor is very small and VCC = VBB = 16 V, also find the voltage gain and power gain of circuit making appropriate assumptions.


 36

Suppose a ‘n’-type wafer is created by doping Si crystal having 5 × 1028 atoms/m3 with 1ppm concentration of As. On the surface 200 ppm Boron is added to create ‘P’ region in this wafer. Considering ni = 1.5 × 1016 m–3, (i) Calculate the densities of the charge carriers in the n & p regions. (ii) Comment which charge carriers would contribute largely for the reverse saturation current when diode is reverse biased.

 37

An X-OR gate has following truth table:

It is represented by following logic relation



Build this gate using AND, OR and NOT gates.