Both sides previous revisionPrevious revisionNext revision | Previous revisionNext revisionBoth sides next revision |
university:courses:electronics:electronics-lab-32 [24 Jul 2017 16:11] – change amplitude value to peak-peak Antoniu Miclaus | university:courses:electronics:electronics-lab-32 [10 Nov 2017 02:40] – added scope shot for vout and vin on both 220uF and 4.7uF Dann Kristofer Bautista |
---|
| |
AWG1 is connected as V<sub>IN</sub> and should be configured as a sine wave with an amplitude greater than 6 volts, zero offset and a frequency of 100 Hz. The scope inputs are used to monitor various points around the circuit such as V<sub>IN</sub>, V<sub>OUT</sub>, the voltage across R<sub>S</sub> and thus the current through R<sub>S</sub>, and the gate of M<sub>1</sub>. | AWG1 is connected as V<sub>IN</sub> and should be configured as a sine wave with an amplitude greater than 6 volts, zero offset and a frequency of 100 Hz. The scope inputs are used to monitor various points around the circuit such as V<sub>IN</sub>, V<sub>OUT</sub>, the voltage across R<sub>S</sub> and thus the current through R<sub>S</sub>, and the gate of M<sub>1</sub>. |
| |
| {{ :university:courses:electronics:active_rectifiers_hardware_setup.png |}} |
| |
| <WRAP centeralign> Figure 2 Active half wave rectifier with self-powered op amp Bread Board Circuit </WRAP> |
| |
=====Procedure:===== | =====Procedure:===== |
Start by using the large value 220 uF capacitor for C<sub>1</sub>. The 220 uF and 4.7 uF capacitors are polarized so be sure to connect the positive and negative terminals to your circuit correctly. | Start by using the large value 220 uF capacitor for C<sub>1</sub>. The 220 uF and 4.7 uF capacitors are polarized so be sure to connect the positive and negative terminals to your circuit correctly. |
| |
Use the two scope inputs to monitor the input AC waveform at V<sub>IN</sub> and the DC output wave form at V<sub>OUT</sub>. VOUT should be very close to the peak value of V<sub>IN</sub>. Now replace the large 220 uF capacitor with the much smaller 4.7 uF capacitor. Observe the change in the waveform seen at V<sub>OUT</sub>. When is V<sub>OUT</sub> closest in value to V<sub>IN</sub> and compare that interval of the AC input cycle with the voltage at the gate of transistor M<sub>1</sub>. | Use the two scope inputs to monitor the input AC waveform at V<sub>IN</sub> and the DC output wave form at V<sub>OUT</sub>. VOUT should be very close to the peak value of V<sub>IN</sub>. Now replace the large 220 uF capacitor with the much smaller 4.7 uF capacitor. Observe the change in the waveform seen at V<sub>OUT</sub>. When is V<sub>OUT</sub> closest in value to V<sub>IN</sub> and compare that interval of the AC input cycle with the voltage at the gate of transistor M<sub>1</sub>. \\ |
| |
| {{ :university:courses:electronics:active_rectifiers_scopeshot_220uf.png |}} |
| <WRAP centeralign> Figure 3 Vout and Vin at 220uF capacitor </WRAP> |
| {{ :university:courses:electronics:active_rectifiers_scopeshot_4.7uf.png |}} |
| <WRAP centeralign> Figure 3 Vout and Vin at 4.7uF capacitor </WRAP> |
| |
With scope channel 2 connected across shunt the 10Ω resistor R<sub>S</sub>, use the Measure feature to obtain the peak and average value of the current. Compare the average value with the DC current in the 2.2 KΩ load resistor R<sub>L</sub> you calculate based on the voltage you measure at V<sub>OUT</sub>. Repeat this measurement for both the 220 uF and 4.7 uF capacitor values. How do the peak and average values compare between these two capacitor values? | With scope channel 2 connected across shunt the 10Ω resistor R<sub>S</sub>, use the Measure feature to obtain the peak and average value of the current. Compare the average value with the DC current in the 2.2 KΩ load resistor R<sub>L</sub> you calculate based on the voltage you measure at V<sub>OUT</sub>. Repeat this measurement for both the 220 uF and 4.7 uF capacitor values. How do the peak and average values compare between these two capacitor values? |