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university:courses:electronics:electronics-lab-1 [05 Mar 2019 10:51]
amiclaus [Non-Inverting Amplifier:]
university:courses:electronics:electronics-lab-1 [23 Aug 2019 11:37] (current)
andreeapop amplitude peak-to-peak
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 === Procedure: === === Procedure: ===
  
-Use the first waveform generator as source Vin to provide a 2V amplitude, 1 kHz sine wave excitation to the circuit. Configure the scope so that the input signal is displayed on channel 2 and the output signal is displayed on channel 1.Export a plot of the two resulting waveforms and include it your lab report, noting the parameters of the waveforms (peak values and the fundamental time-period or frequency). Your waveforms should confirm the description of this as a “unity-gain” or “voltage follower” circuit.+Use the first waveform generator as source Vin to provide a 2V amplitude ​peak-to-peak, 1 kHz sine wave excitation to the circuit. Configure the scope so that the input signal is displayed on channel 2 and the output signal is displayed on channel 1.Export a plot of the two resulting waveforms and include it your lab report, noting the parameters of the waveforms (peak values and the fundamental time-period or frequency). Your waveforms should confirm the description of this as a “unity-gain” or “voltage follower” circuit.
  
 A plot example is presented in Figure 1.4. A plot example is presented in Figure 1.4.
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 <WRAP centeralign>​ Figure 1.5 Slew Rate </​WRAP>​ <WRAP centeralign>​ Figure 1.5 Slew Rate </​WRAP>​
  
-Set the waveform generator to a square wave signal with a 2V amplitude and increase the frequency until you see a significant departure from ideal behavior, that is, when the output starts looking more like a trapezoid than a square wave. You will likely need to adjust the time scale (Sec/Div) on the scope display to see this. Export a plot of the output waveforms at this point and measure its 10-90% rise time (and 90-10% fall time) as defined in figure 1.5. Also note the peak-to-peak voltage of the output signal. Compute and record the slew rate for both rising and falling outputs according to your measurements. Comment on why the response to rising and falling edges might be different.+Set the waveform generator to a square wave signal with a 2V amplitude ​peak-to-peak ​and increase the frequency until you see a significant departure from ideal behavior, that is, when the output starts looking more like a trapezoid than a square wave. You will likely need to adjust the time scale (Sec/Div) on the scope display to see this. Export a plot of the output waveforms at this point and measure its 10-90% rise time (and 90-10% fall time) as defined in figure 1.5. Also note the peak-to-peak voltage of the output signal. Compute and record the slew rate for both rising and falling outputs according to your measurements. Comment on why the response to rising and falling edges might be different.
  
 A waveform that exemplifies the slew rate is presented in figure 1.6. A waveform that exemplifies the slew rate is presented in figure 1.6.
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 Turn off the power supplies and add the resistors to your circuit as shown in figure 1.7 (note we have not changed the op-amp connections here, we’ve just flipped the op-amp symbol relative to figure 1.2). Turn off the power supplies and add the resistors to your circuit as shown in figure 1.7 (note we have not changed the op-amp connections here, we’ve just flipped the op-amp symbol relative to figure 1.2).
  
-Turn on the power supplies and set the waveform generator to a 1 kHz sine signal with a 4V amplitude. Use the scope to simultaneously observe Vin and Vout and record the amplitudes in your lab report.+Turn on the power supplies and set the waveform generator to a 1 kHz sine signal with a 4V amplitude ​peak-to-peak. Use the scope to simultaneously observe Vin and Vout and record the amplitudes in your lab report.
  
 Remove the 10 kΩ load and substitute a 1 kΩ resistor instead. Record the amplitude. Remove the 10 kΩ load and substitute a 1 kΩ resistor instead. Record the amplitude.
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 Now assemble the inverting amplifier circuit shown in figure 1.9 using R<​sub>​2</​sub>​ = 4.7kΩ . Remember to shut off the power supply before assembling a new circuit. Cut and bend the resistor leads as needed to keep them flat against the board surface, and use the shortest jumper wires for each connection (as in figure 1.1). Remember, the breadboard gives you a lot of flexibility. For example, the leads of resistor R<​sub>​2</​sub>​ do not necessarily have to bridge over the op amp from pin 2 to pin 6; you could use an intermediate node and a jumper wire to go around the device instead. Now assemble the inverting amplifier circuit shown in figure 1.9 using R<​sub>​2</​sub>​ = 4.7kΩ . Remember to shut off the power supply before assembling a new circuit. Cut and bend the resistor leads as needed to keep them flat against the board surface, and use the shortest jumper wires for each connection (as in figure 1.1). Remember, the breadboard gives you a lot of flexibility. For example, the leads of resistor R<​sub>​2</​sub>​ do not necessarily have to bridge over the op amp from pin 2 to pin 6; you could use an intermediate node and a jumper wire to go around the device instead.
  
-Turn on the power supplies and observe the current draw to be sure there are no accidental shorts. Now adjust the waveform generator to produce a 2 volt amplitude, 1 kHz sine wave at the input (Vin), and again display both the input and output on the oscilloscope. Measure and record the voltage gain of this circuit, and compare to the theory that was discussed in class. Export a plot of the input/​output waveforms to be included your lab report.+Turn on the power supplies and observe the current draw to be sure there are no accidental shorts. Now adjust the waveform generator to produce a 2 volt amplitude ​peak-to-peak, 1 kHz sine wave at the input (Vin), and again display both the input and output on the oscilloscope. Measure and record the voltage gain of this circuit, and compare to the theory that was discussed in class. Export a plot of the input/​output waveforms to be included your lab report.
  
 {{:​university:​courses:​electronics:​inverting_amp-bb.png|}} {{:​university:​courses:​electronics:​inverting_amp-bb.png|}}
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 === Procedure: === === Procedure: ===
  
-Use the first waveform generator as source Vin to provide a 2V amplitude, 1 kHz sine wave excitation to the circuit. Configure the scope so that the input signal is displayed on channel 2 and the output signal is displayed on channel 1.+Use the first waveform generator as source Vin to provide a 2V amplitude ​peak-to-peak, 1 kHz sine wave excitation to the circuit. Configure the scope so that the input signal is displayed on channel 2 and the output signal is displayed on channel 1.
  
 A plot example is presented in Figure 1.10. A plot example is presented in Figure 1.10.
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 With the power turned off, modify your inverting amplifier circuit as shown in figure 1.12. Use the second waveform generator output for Vin2. Turn the amplitude all the way down to zero so that you can adjust up from zero during the experiment. With the power turned off, modify your inverting amplifier circuit as shown in figure 1.12. Use the second waveform generator output for Vin2. Turn the amplitude all the way down to zero so that you can adjust up from zero during the experiment.
  
-Now apply a 2 volt amplitude sine wave for Vin1 and 1 volts DC for Vin2. Observe and record the input/​output waveforms on the oscilloscope screen. Pay close attention to the ground signal level of the output channel on the oscilloscope screen. When used in this way, such a circuit could be called a level shifter.+Now apply a 2 volt amplitude ​peak-to-peak ​sine wave for Vin1 and 1 volts DC for Vin2. Observe and record the input/​output waveforms on the oscilloscope screen. Pay close attention to the ground signal level of the output channel on the oscilloscope screen. When used in this way, such a circuit could be called a level shifter.
  
 Adjust the DC offset of waveform generator W1 (Vin1) until Vout has zero DC component. Estimate the required DC offset by observing the input waveform on the scope (note: it is not Vin2 , be sure to understand why). Adjust the DC offset of waveform generator W1 (Vin1) until Vout has zero DC component. Estimate the required DC offset by observing the input waveform on the scope (note: it is not Vin2 , be sure to understand why).
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 === Procedure: === === Procedure: ===
  
-Use the first waveform generator as source Vin to provide a 2V amplitude, 1 kHz sine wave excitation to the circuit. The second waveform generator is used to generate 1V constant voltage. Configure the scope so that the input signal is displayed on channel 2 and the output signal is displayed on channel 1.+Use the first waveform generator as source Vin to provide a 2V amplitude ​peak-to-peak, 1 kHz sine wave excitation to the circuit. The second waveform generator is used to generate 1V constant voltage. Configure the scope so that the input signal is displayed on channel 2 and the output signal is displayed on channel 1.
  
 A plot example is presented in Figure 1.13. A plot example is presented in Figure 1.13.
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 Assemble the non-inverting amplifier circuit shown in figure 1.15. Remember to shut off the power supplies before assembling the new circuit. Start with R<​sub>​2</​sub>​ = 1kΩ. Assemble the non-inverting amplifier circuit shown in figure 1.15. Remember to shut off the power supplies before assembling the new circuit. Start with R<​sub>​2</​sub>​ = 1kΩ.
  
-Apply a 2 volt amplitude, 1 kHz sine wave at the input, and display both input and output on the scope. Measure the voltage gain of this circuit, and compare to the theory discussed in class. Export a plot of the waveforms and include it in your lab report.+Apply a 2 volt amplitude ​peak-to-peak, 1 kHz sine wave at the input, and display both input and output on the scope. Measure the voltage gain of this circuit, and compare to the theory discussed in class. Export a plot of the waveforms and include it in your lab report.
  
 Increase the feedback resistor (R<​sub>​2</​sub>​) from 1 kΩ to about 5 kΩ. What is the gain now? Increase the feedback resistor (R<​sub>​2</​sub>​) from 1 kΩ to about 5 kΩ. What is the gain now?
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 === Procedure: === === Procedure: ===
-Use the first waveform generator as source Vin to provide a 2V amplitude, 1 kHz sine wave excitation to the circuit. Configure the scope so that the input signal is displayed on channel 2 and the output signal is displayed on channel 1.+Use the first waveform generator as source Vin to provide a 2V amplitude ​peak-to-peak, 1 kHz sine wave excitation to the circuit. Configure the scope so that the input signal is displayed on channel 2 and the output signal is displayed on channel 1.
  
 A plot example is presented in Figure 1.16. A plot example is presented in Figure 1.16.
university/courses/electronics/electronics-lab-1.txt · Last modified: 23 Aug 2019 11:37 by andreeapop