EGR203 Electric and Electronic Circuits Assignment 7

1. Find the current i in the circuit below with R₁ = 60 kΩ, R₂ = 30 kΩ, R₃ = 20 kΩ, and V_i = 120 mV.

   

2. Find the voltage V_o in the circuit below with R₁ = 20 kΩ, R₂ = 60 kΩ, R₃ = 40 kΩ, R_F = 120 kΩ, and V_i = 70 mV.

   

3. Find an expression for the output V_o in the circuit below. What mathematical operation does the circuit perform?

   

4. Simulate the following circuit in Multisim. Use a LM348D op-amp with ±12-volt power. Let R_S = 4 kΩ, R₁ = 40 kΩ and R₂ = 10 kΩ. Measure the AC gain and phase for an input voltage of 50 mV AC at frequencies of 10 kHz and 100 kHz. Run an AC analysis between 10 kHz and 100 kHz.

   

5. Given the following circuit of an external resistor R_S = 200 Ω and a diode with turn-on voltage V_T = 0.7 V and internal resistance R_D = 1 Ω, find the voltage V_D and current i_D for a source voltage V_S = 12 V.

   

6. Given the following circuit, in which R₁ = R₂ = R₃ = 100 Ω, a diode with turn-on voltage V_T = 0.7 V, and source voltage V_S = 5 V. Find i_D.

   

   Hint: Consider the Thévenin equivalent circuit.

7. Solve the previous problem in Multisim, assuming a 1N4148 diode.

Maintained by John Loomis, last updated 20 October 2010