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| Both sides previous revisionPrevious revision | Next revisionBoth sides next revision | ||
| university:courses:engineering_discovery:lab_8 [24 Aug 2016 17:56] – Jonathan Pearson | university:courses:engineering_discovery:lab_8 [07 Sep 2016 21:25] – Jonathan Pearson | ||
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| - Scale the Y-axis of the X-Y plot using the mouse and right mouse button such that the measured current ranges between 0.00 A and 0.09 A (90 mA) | - Scale the Y-axis of the X-Y plot using the mouse and right mouse button such that the measured current ranges between 0.00 A and 0.09 A (90 mA) | ||
| - Observe the LED flashing, the shape of the measured current waveform, and the shape of the X-Y plot, which is a plot of the diode current vs. diode voltage | - Observe the LED flashing, the shape of the measured current waveform, and the shape of the X-Y plot, which is a plot of the diode current vs. diode voltage | ||
| - | - Increase the peak level of the applied | + | - Increase the peak level of the applied |
| - Describe what is happening in the measured current and X-Y plot | - Describe what is happening in the measured current and X-Y plot | ||
| - Change the Y-axis scale to range between 0.00 A and 0.20 A (200 mA) | - Change the Y-axis scale to range between 0.00 A and 0.20 A (200 mA) | ||
| - | - Increase the peak level of the applied | + | - Increase the peak level of the applied |
| - Describe what is happening in the measured current and X-Y plot; why does the current flatten out at approximately 200 mA? | - Describe what is happening in the measured current and X-Y plot; why does the current flatten out at approximately 200 mA? | ||
| - | - Observe that there is a difference in the voltage vs. current trajectory in the X-Y plot between increasing current and decreasing current when the sawtooth | + | - Observe that there is a difference in the voltage vs. current trajectory in the X-Y plot between increasing current and decreasing current when the triangle wave peak level is at 2.4 V (it may be helpful to expand the X-axis scale to better observe this); this difference is called " |
| - Explain why the hysteresis occurs | - Explain why the hysteresis occurs | ||
| - Repeat the above procedure for the green and red LEDs | - Repeat the above procedure for the green and red LEDs | ||
| - Observe and describe any differences seen in the behavior of the three different LEDs | - Observe and describe any differences seen in the behavior of the three different LEDs | ||
| - | - Change the amplitude of the sawtooth | + | - Change the amplitude of the triangular |
| - Replace the LED with a 1N914 signal diode as shown in the following schematic{{ university: | - Replace the LED with a 1N914 signal diode as shown in the following schematic{{ university: | ||
| - | - Increase the peak level of the applied | + | - Increase the peak level of the applied |
| - Observe the exponential shape of the diode current versus voltage characteristic and that the knee of the curve -- commonly referred to as the "cut in" voltage -- is nominally between 0.70 V and 0.75 V | - Observe the exponential shape of the diode current versus voltage characteristic and that the knee of the curve -- commonly referred to as the "cut in" voltage -- is nominally between 0.70 V and 0.75 V | ||
| - Set up Channel A to source 5 V DC and Channel B to measure voltage | - Set up Channel A to source 5 V DC and Channel B to measure voltage | ||
university/courses/engineering_discovery/lab_8.txt · Last modified: 03 Jan 2018 19:36 by Doug Mercer