DG CIRCUIT CHALLENGE SOLVING FOR DC CIRCUIT COMPONENT VALUES

Draw the DC circuit:  b)DC computations: Compute the DC collector current of each transistor. I_C 1 = ________________________ mA I_C 2= ________________________ Calculations:  c)Draw the AC circuit and compute gm, r_pi for the system. g_m 1= _______________________ mA/V r_pi 1 = _______________________ kohms g_m 2= _______________________ mA/V r_pi 2 = _______________________ kohms AC circuit:  Calculations: d)Compute the gain A_v=Vo/Vi at the operational band (for sufficiently high frequency) Gain = A_v = ______________________________ Computations:

1) In the context of semiconductors, describe the following:(a) Intrinsic and extrinsic semiconductor. (b) Drift velocity of carriers.(c) Band-gap energy.(d) Frequency of light emitted by an LED.

A PWM signal changes with a voltage of -15 and 15 volts while it is desirable to produce an effective (average) voltage of the PWM signal of 9 volts. The duty cycle that must be generated is