4.2 Exercise: instrumenting simulated circuits in national

Approximate time to complete: 20 minutes

This exercise will demonstrate the interactive simulator, and virtual instruments. By the end of thisexercise, users will be familiar with placing instruments, opening their front panels, and configuring various options.

Objectives

• Learn how to place and connect virtual instruments.
• Gain experience configuring instruments.

Procedure

• Load circuit 40kFilter2.ms9 . Refer to while performing steps 2 - 4.
• Replace the Clock Source with a Function Generator. Once placed, double-click to open the instrument panel and adjust itssettings as follows:

• Waveform = sinewave
• Amplitude = 1 V
• Frequency = 40 kHz

• Close the instrument panel.
• Attach the Bode plotter between the input and output nodes. Double-click to open the instrument and adjust its settings asfollows, then simulate and observe the output:

• Set Magnitude
• Horizontal I (Initial) = 1 kHz, F (Final) = 1 MHz
• Vertical I (Initial) = -50 dB, F (Final) = 10 dB

• Attach an oscilloscope to monitor the input and output voltages.Double-click on the oscilloscope icon to adjust itssettings as follows:

• Set Timebase = 20 us/Div
• Channel A= 1 V/Div
• Channel B = 1 V/Div

• The color of the wire segment connected to an instrument controls the color of the trace on the instrument display. Makesure that the wires from the output of the op-amp are blue. If they are not, then right-click on a wire segment and choose“Wire Color”to change the setting. Now, simulate and observe the output.
• Change the value of the Potentiometer (R3) by pressing“A”to increase the resistance and“Shift-A”to decrease the resistance during simulation. Observe the response on the oscilloscope. Note:The Bode Plot response will be updated only after you re-simulate the circuit.

• While the simulation is still running, use the“Measurement Probe”to view the voltage levels in the circuit. It is found at the end of the instrument panel.