EE 321L Analog Electronics Laboratory Fall 2010Lab 5Diode Rectifier CircuitsPre-Lab1. Find the junction capacitances for the 1N4001 and the 1N4148.2. Write the equation you need to compute the correct resistor size in step 14.3. Derive a formula for estimating the size of the ripple from the capacitor size, the resistorsize, and the period of the output (we did t his in class).In this la b we will look at the voltage characteristics of rectifier circuits built from diodes.Half-wave rec tifier1. Build the half-wave rectifier, using a 1N4001, and the f unction generator as input.2. Apply voltage inputs between 1 V and 20 V at a frequency of 100 Hz. Plot two sampleinput and output waveforms, one set for small voltage, one for large voltage.3. Make several measurements of, and plot, the peak output versus the amplitude of theinput.4. Discuss the r esults.5. For a 1 V amplitude signal, increase the frequency to between 10 kHz and 1 MHz. Plotone or two examples of how the output changes as you increase the frequency. Forexample, make a plot at low frequency with some number of periods across the screen,then a plot at high frequency with the same number of periods across the screen, andcompare the two. What do you see?6. Replace the diode with a 1N4148. What changes?7. What is the reason for the difference? Hint: diodes have capacitance associated withtheir junction, a nd the junction capacitance of the 1N4001 is larger than the junctioncapacitance of the 1N4148.1EE 321L Analog Electronics Laboratory Fall 2010Super diode8. Build the super-diode circuit with the 1N4001 and using the function generator asinput again. Make a note of the supply voltages you choose for the op-amp.9. Apply inputs at 100 Hz with varying amplitudes as in step 2. Plot one example showingvI, vA, and vO. Since the scopes have only two inputs, make two plots with vIon both.10. Discuss the r eason why vAlooks the way it does. How is the output different from thehalf-wave rectifier?Bridge rectifier11. Build the bridge rectifier using 1N4001 diodes. Use a transformer to float the entirefunction generator, and attach the oscilloscope ground as shown in the figure.12. Apply both a small and a large amplitude input voltage at 100 Hz and plot the inputand output together. To get the input to the oscilloscope you will need to connect thesecond input probe and ground to the input through capacitors.13. What is different about this output, compared to the output of the half-wave rectifier?14. Attach a load and a large capacitor to t he output. Size the resistor to g et a time-constant which is many times (10-100) the period of the output.15. Measure the ripple (AC couple) and compare to the theoretical prediction from class.2EE 321L Analog Electronics Laboratory Fall 201016. Next, choose a resistor to make the time-constant only 2 times the period of the output,and repeat the measurement and calculation.17. Is the formula from class more accurate for large or small amplitude
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