Assignment Questions -

Instructions: Answer the questions below and show all steps.

Q1. Consider the full-wave rectifier circuit below. Use a constant voltage drop model for the diodes with V_D = 0.7 V. Let v₁ = 12 sin(2π(100)t).

a. Calculate the average value of v_out using integration with angle in radians as the integration variable, not time.

b. A capacitor is placed across R1 to reduce the ripple to 10 mVp-p. Find the capacitor value.

c. Calculate the approximate average v_out value assuming triangular ripple waveform.

Q2. Simulate the circuit of question 1.

a. Simulate the original circuit of part 1(a) for 20ms and plot the output. Include the plot and schematic with your homework.

Use cursors to find angle at which the v_out waveform first exceeds 0V and the angle at which it returns to zero volts during the first 5 ms interval. You will need to convert from time to radian angle.

Have SPICE determine the average value of the waveform. In LTspice, mouse over the name of the waveform at the top of the plot and left click while pressing the Ctrl key. The average value will be displayed in a box. You do not need a screen shot, just record the value.

b. Simulate the part 1(a) circuit for 16 ms and find the average value. Why is it different than the value found in 2(b)? You do not need a screen shot, just record the value.

Q3. Design a 2-sided limiting circuit using a resistor, two diodes and two dc power supplies with a 2 kΩ resistor load attached. The limited output voltage range is -3V to +4V.

The gain must be 0.9 V/V in the region where the diodes are not limiting. Use a constant voltage drop model for the diodes with VD = 0.7 V. Determine the value of R1 and the two voltage sources. Sketch the schematic.

Q4. A PMOS transistor having parameters |V_tp| = 0.8V and k'_p(W/L) = 1.5 mA/V² must operate in saturation for a 200 µA drain current.

a. Determine the v_GS and minimum v_DS required.

b. Determine the value of k'_p if W = 2 μm and L = 500 nm.

Q5. Find RS and RD to create a 5 mA drain current and a drain voltage of 0V. The MOSFET has V_tp = -0.5V, µ_pC_ox = 0.8 mA/V², L=1 µm, and W=8 µm.

Q6. Consider the circuit below. The capacitors are infinite and can be considered ac short circuits.

a. Find the voltages at the gate, drain and source as well as the drain current. Let V_tn = 0.6V, k'_n(W/L) = 3 mA/V².

b. Find g_m and the common-source voltage gain Vout/Vin. Ignore MOSFET output resistance r_o.

c. Sketch the ac equivalent model of the circuit.

Attachment:- Assignment Files.rar