EBBZ0002&PEE20006 LABORATORY 3: TRANSIENT AND FREQUENCY RESPONSES OF RC CIRCUITS 1. Student Name 2. Student Name 3. Stud

[answerhappygod]

Ebbz0002 Pee20006 Laboratory 3 Transient And Frequency Responses Of Rc Circuits 1 Student Name 2 Student Name 3 Stud 1 (71.01 KiB) Viewed 20 times

Ebbz0002 Pee20006 Laboratory 3 Transient And Frequency Responses Of Rc Circuits 1 Student Name 2 Student Name 3 Stud 2 (63.54 KiB) Viewed 20 times

Ebbz0002 Pee20006 Laboratory 3 Transient And Frequency Responses Of Rc Circuits 1 Student Name 2 Student Name 3 Stud 3 (44.56 KiB) Viewed 20 times

Ebbz0002 Pee20006 Laboratory 3 Transient And Frequency Responses Of Rc Circuits 1 Student Name 2 Student Name 3 Stud 4 (47.93 KiB) Viewed 20 times

Ebbz0002 Pee20006 Laboratory 3 Transient And Frequency Responses Of Rc Circuits 1 Student Name 2 Student Name 3 Stud 5 (78.5 KiB) Viewed 20 times

EBBZ0002&PEE20006 LABORATORY 3: TRANSIENT AND FREQUENCY RESPONSES OF RC CIRCUITS 1. Student Name 2. Student Name 3. Student Name ID# ID# ID# Aim: To study the transient and frequency responses of Single-Time-Constant (STC) RC circuits. Introduction The current ic in a capacitor is given by: (t)-cdv_(0) where v.(t) is the voltage across the capacitor dt The voltage ve across an inductor is given by: 4.0L di (1) where 1, () is the current in the inductor. The voltage across a capacitor cannot change instantaneously, and the current in an inductor cannot change instantaneously. In the circuit of Figure 1, the switch is initially at position 1and the capacitor is uncharged. R w Us 5V I + uc Figure 1 Att = 0, the switch is flipped to position 2 which connects V, to the RC circuit. The capacitor charges up, and its voltage increases exponentially towards V., with a time constant, (= = RC). After one millisecond, the switch is put back into position 1. The capacitor now discharges, and its voltage decreases exponentially towards OV. The switch is toggled at this rate between the two pole positions. EEE 20002 & EEE20006 - Lab 3 Page 1
For the charging interval, at t=t (assuming at t=0, Vc(O) = OV), Vc(t) = 0.632*Vs = 3.16V (for V. = 5V). For the discharging interval, at t=ı (assuming at t=0, vc(O) = Vs), vc(t) = 0.368"V, = 1.84V (for Vs = 5V). Required Equipment Prototyping board Oscilloscope (CRO) Digital Multimeter (DMM) R = 10k 2 resistor Signal Generator C = 15nF capacitor Preliminaries (20% of this lab.) Workings for your preliminaries must be shown in the space provided. A. For the circuit of Figure 1, find its time constant, t. TE B. Complete Table 1. Table 1 Time Current i(t) Voltage across the capacitor vc i(0) = Vc(0) = Voltage across the resistor VR VR(0) = 0 0* i(0*) = Vc(O) = VR(0*) = Change in voltage across the capacitor w.r.t. time dvc -(0) dt dv. (0*)= dt dv -(0.3ms) dt 0.3ms i(0.3ms) = Vc(0.3ms) = VR(0.3ms) = C. Obtain expressions for the voltage across the capacitor, Ve(t) for Charging interval (0 to 1.0ms):
3 D. Using the expressions from C, complete Table 2 below. Table 2 Time 0.51 5t 10t IVO τ 26t E. Sketch the expected voltage waveform across the capacitor (superimposed on the given Vxy waveform), clearly indicating the locations (for charging and discharging intervals) oft on your waveform. 5V VXY 0 0 1.0 2.0 time (ms) OK (supervisor's initials and grade, in %) EEE20002 & EEE20006 - Lab 3 Page 3 3
EEE20002 & EEE20006 - Lab 3 Page 4 (d) From Table 3, sketch the frequency response curve versus frequency) of the circuit. Frequency (Hertz) Plot of 們 vs frequency (e) From part (d), estimate the -3 dB frequency, fc. fc is the frequency at which the gain is 0.707 of the gain in the passband. fc = (f) What observation can be made between the time (transient) response and the frequency response?
Part 1 Low-pass STC RC circuit Construct the circuit in Figure 1. Instead of the 5V source and switch, the output of a signal generator is connected across nodes X and Y. The signal generator is set to square wave mode (and amplitude swings of 0 to 5V), to simulate the switching back and forth between the charging and discharging processes. The period (T) of the square wave should be chosen so that T >> t to allow for the capacitor to be fully charged or fully discharged. A suitable value for T is around 2ms. Connect one channel of the CRO to display the voltage Vxy, and the other channel to monitor the voltage across the capacitor. (a) From the waveforms, measure the actual t of the circuit. Briefly explain how you measure T. (b) Sketch Vxy over one period, and on it, superimpose the waveform across the capacitor. The waveforms should be clearly labelled to include information on 1 and Ve(t). Label the axes. Vxy and vc(t) waveforms (c) Change the mode on the signal generator to sine-wave, with a peak-to-peak amplitude of 2V. Measure the peak-to-peak amplitude of the voltage across the capacitor for various frequencies (100, 400, 800, 1000, 1500, 2000, and 5000 Hz), and complete Table 3. 100 Table 3 400 800 1000 1500 2000 Frequency (in Hertz) Vc (peak-to-peak) 5000