Difference between revisions of "PIC32MX: Sinusoidal Analog Output"
Andrew Long (talk | contribs) |
Andrew Long (talk | contribs) |
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Overview: |
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How do we obtain analog output? ie PWM (brief description) |
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TOC |
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How do we get sinusoidal output? ie divide up sinusoid into N points, scale duty cycle accordingly |
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General discussion about how cutoff frequency, number of points period (N) and the RC time constant matter. |
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State that the examples here have PWM at 20kHz. |
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__TOC__ |
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==Cutoff Frequency== |
==Cutoff Frequency== |
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How to choose cut-off frequency -- what is the equation? |
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Show picture if you choose your frequency to high and if you choose your frequency to low. |
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Say something about how the amplitude decreases with high frequency |
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==Number of Points Per Period== |
==Number of Points Per Period== |
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Show Pictures of number of points to small - discuss that you see the capacitor charging |
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Show picture of good number of points |
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==RC Time Constant== |
==RC Time Constant== |
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Explain that a large RC time constant smooths the plot but introduces a phase lag. |
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Show the pictures you provided in the presentation. |
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==Sample Code== |
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Include your sample code (this may need cleaned up a bit). |
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To make a box around the code, put a 'space' in front of each line. |
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Revision as of 10:47, 20 April 2010
Overview:
How do we obtain analog output? ie PWM (brief description)
How do we get sinusoidal output? ie divide up sinusoid into N points, scale duty cycle accordingly
General discussion about how cutoff frequency, number of points period (N) and the RC time constant matter.
State that the examples here have PWM at 20kHz.
Cutoff Frequency
How to choose cut-off frequency -- what is the equation?
Show picture if you choose your frequency to high and if you choose your frequency to low.
Say something about how the amplitude decreases with high frequency
Number of Points Per Period
Show Pictures of number of points to small - discuss that you see the capacitor charging
Show picture of good number of points
RC Time Constant
Explain that a large RC time constant smooths the plot but introduces a phase lag.
Show the pictures you provided in the presentation.
Sample Code
Include your sample code (this may need cleaned up a bit).
To make a box around the code, put a 'space' in front of each line.
