ECE 202 Lab Report: Experiment 4 - RC Circuits - Prof. Olivera K. Notaros, Lab Reports of Electrical and Electronics Engineering

Download ECE 202 Lab Report: Experiment 4 - RC Circuits - Prof. Olivera K. Notaros and more Lab Reports Electrical and Electronics Engineering in PDF only on Docsity! ECE 202 – Experiment 4 – Lab Report 4-1 STEP RESPONSE OF RC CIRCUITS YOUR NAME______________________ GTA’S SIGNATURE_________________ LAB MEETING TIME______________ THE HP IMPEDANCE ANALYZER The HP Impedance Analyzer is found in the Circuits Lab (Engineering C105) on a table next to the hallway connecting to the Electronics Lab. With it, you can determine a circuit element’s value, whether it be a resistor, capacitor, or inductor, and also measure the magnitude and phase of an element’s impedance. The machine will also show how these quantities vary with frequency. Chapter 3 of the instruction manual (on the table) describes the front panel functions but you probably can just figure them out by trial and error. Get a capacitor and try the following. To measure this capacitor’s value: Set the frequency of the analyzer to 1 kHz. Insert the capacitor into the test fixture and measure the impedance magnitude and its angle. The angle of your capacitor should be near -90. If the angle is not close to one of these values, get a different capacitor. Impedance Angle (measured) = __________ deg Now change the analyzer’s settings so that capacitance is displayed. C(measured) = __________ F You might be curious to explore how the capacitance value depends on frequency from 0.1 to 100 kHz. You might also like to try measuring inductor values with the Analyzer; the impedance angel of an inductor should be near +90. It is particularly interesting to see how the inductor’s impedance angle varies with frequency; often, the value improves with increasing frequency. ECE 202 – Experiment 4 – Lab Report 4-2 1. Build the following two circuits: a) DIFFERENTIATOR b) INTEGRATOR and observe their output waveforms when you apply a 5 kHz square wave of 5 volt amplitude to the input. Set the function generator to 5 kHz, 5 Vpp, and 2.5 V DC level. To begin, choose values of C to satisfy: 5(RC) = T1/2 for the differentiator, and RC = 5(T1/2) for the integrator, where T1 is the period of vi(t). NOTE: This is called the “5 time constants rule of thumb” and gives a good estimate of the time required for the output signal, v(t), to achieve steady state during one period of the input signal. Now change the input square wave frequency by a factor of five, decreasing f for circuit a) and increasing it for circuit b), and record your observations. Attach sketches of v(t) for each case. Do these circuits justify their titles? Explain.