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university:courses:electronics:electronics-lab-12sg [24 Jul 2017 15:38] – change amplitude value to peak-peak Antoniu Miclausuniversity:courses:electronics:electronics-lab-12sg [25 Jun 2020 22:07] (current) – external edit 127.0.0.1
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 Set the AWG 1 to the Following:\\ Set the AWG 1 to the Following:\\
-  * Amplitude = 3.6V\\+  * Amplitude (peak-to-peak) = 3.6V\\
   * Offset = 0V\\   * Offset = 0V\\
   * Frequency = 1KHz\\   * Frequency = 1KHz\\
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 Adjust the 500 Ω potentiometer, R<sub>6</sub>, for the best symmetry in the output sine wave shape. Using the FFT display and looking for the minimum even order distortion may be a good way to test the quality of the output sine wave. You may want to adjust the amplitude and DC offset of the input triangle wave to see if that can improve the odd order harmonics in the output. Adjust the 500 Ω potentiometer, R<sub>6</sub>, for the best symmetry in the output sine wave shape. Using the FFT display and looking for the minimum even order distortion may be a good way to test the quality of the output sine wave. You may want to adjust the amplitude and DC offset of the input triangle wave to see if that can improve the odd order harmonics in the output.
  
-{{ :university:courses:electronics:a_sin_f1.png?650 |}}+{{ :university:courses:electronics:a_sin_f1.png?650 |}} 
  
 <WRAP centeralign> Figure 1, Differential pair triangle to sine converter </WRAP> <WRAP centeralign> Figure 1, Differential pair triangle to sine converter </WRAP>
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 Comparing the two Taylor series will see that they are both linear to first order. What this means is that if we apply a triangle wave to a differential pair with a hyperbolic tangent transfer function, and keep the amplitude low, that is on the order of 2V<sub>T</sub>, what you get out should be nearly indistinguishable from a sine wave. The purpose of the 2.2 kΩ resistor and the 220 Ω resistor at the input of the differential pair (base of Q<sub>1</sub>) is to attenuate the triangle wave signal from the AWG to operate the circuit in the range where the output is as low a distortion sine wave as possible. Comparing the two Taylor series will see that they are both linear to first order. What this means is that if we apply a triangle wave to a differential pair with a hyperbolic tangent transfer function, and keep the amplitude low, that is on the order of 2V<sub>T</sub>, what you get out should be nearly indistinguishable from a sine wave. The purpose of the 2.2 kΩ resistor and the 220 Ω resistor at the input of the differential pair (base of Q<sub>1</sub>) is to attenuate the triangle wave signal from the AWG to operate the circuit in the range where the output is as low a distortion sine wave as possible.
 +=====Hardware Setup=====
 +Connect the circuit shown in figure 1 to a breadboard.
 +{{ :university:courses:electronics:a_sin_nf2.png? |}} 
 +
 +<WRAP centeralign> Figure 2, Differential pair triangle to sine converter breadboard connections </WRAP>
 +With the use of M2K, the output s shown below.
 +{{ :university:courses:electronics:a_sin_nf3.png?500 |}} 
 +
 +<WRAP centeralign> Figure 3, Differential pair triangle to sine converter Scopy plot </WRAP>
 +
  
 =====Triangle Wave Generator===== =====Triangle Wave Generator=====
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 {{ :university:courses:electronics:a_sin_f2.png?650 |}} {{ :university:courses:electronics:a_sin_f2.png?650 |}}
  
-<WRAP centeralign> Figure 2, V-to-F triangle wave generator </WRAP>+<WRAP centeralign> Figure 4, V-to-F triangle wave generator </WRAP>
  
 When connecting the triangle wave output from the AD8226 to the input of the triangle to sine converter, replace the 2.2 KΩ fixed resistor R<sub>1</sub> with a 5 KΩ potentiometer to adjust the signal amplitude for optimal sine wave shape. When connecting the triangle wave output from the AD8226 to the input of the triangle to sine converter, replace the 2.2 KΩ fixed resistor R<sub>1</sub> with a 5 KΩ potentiometer to adjust the signal amplitude for optimal sine wave shape.
 +=====Hardware Setup=====
 +Connect the circuit shown in figure 4 to a breadboard.
 +{{ :university:courses:electronics:a_sin_nf5.png? |}} 
 +
 +<WRAP centeralign> Figure 5, V-to-F triangle wave generator breadboard connections </WRAP>
 +With the use of M2K, the output s shown below. We can adjust the gain resistor of the in-amp (R16) so that the output of the circuit will be in the range instrumentation amplifier supply. In the Scopy plot below, R16 is at 168kΩ.
 +
 +{{ :university:courses:electronics:a_sin_nf6.png?500 |}} 
 +<WRAP centeralign> Figure 6, V-to-F triangle wave generator Scopy plot </WRAP>
 +
 +<WRAP round download>
 +**Resources:**
 +  * Fritzing files: [[downgit>education_tools/tree/master/m2k/fritzing/diffpair_triangle_to_sine_bb | diffpair_triangle_to_sine_bb]]
 +  * LTspice files: [[downgit>education_tools/tree/master/m2k/ltspice/diffpair_triangle_to_sine_ltspice | diffpair_triangle_to_sine_ltspice]]
 +</WRAP>
  
 ====For further reading:==== ====For further reading:====
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 **Return to Lab Activities [[university:courses:electronics:labs|Table of Contents]]** **Return to Lab Activities [[university:courses:electronics:labs|Table of Contents]]**
 +
university/courses/electronics/electronics-lab-12sg.1500903509.txt.gz · Last modified: 24 Jul 2017 15:38 by Antoniu Miclaus

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