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Step of 6 4.092P (a) Consider the diode voltage drop in conduction as, = Draw the following limiter circuit with the input signal in above -0.7 V range. R + + v₁ - Figure 1 Step of 6 From Figure 1 observe that the input voltage is below -0.7V range, the diode in cut-off state. thus the output follows the input. When the input crosses -0.7V then the diode is in conduction mode. Thus, the output is -0.7V Write the expression of output voltage. -0.7V Therefore, the required limiter circuit is shown in Figure 1. Step of 6 (b) Consider the diode voltage drop in conduction as = Draw the following limiter circuit with the input signal limited to above -2.1V range. Connect the three diodes in series. R + 10 kΩ + 0.7 V 0.7 V 0.7 V - - Figure 2 Step of 6 For the input voltage below -2.1V range, the diodes are in cut-off state. Thus, the output follows the input. When the input crosses -0.7V the diodes are in conduction mode. Thus, the output is Write the expression for the output voltage. = Therefore, the required limiter circuit is shown in Figure 2. Step of 6 (c) Consider the diode voltage drop in conduction as For the required limiter circuit the signal should be limited to above +1.4V range. For limiting to +1.4V connect two diodes in series in forward direction to the input. For limiting to -1.4V connect two diodes in series in reverse direction to the input. Draw the following circuit diagram: R + 10 kΩ + D₁ D₃ D₂ - Figure 3 Step of 6 If the input is greater than +1.4V the diodes D, and are in conduction. Thus, the output is +1.4V If the input is less than the diodes and are in conduction. Thus, the output is If the input is in between +1.4V and -1.4V then all the diodes are in cutoff region. Thus, the output follows the input. Write the expression for the output voltage. +1.4V v, >1.4V =