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here is the link for the PSD: "
en.wikipedia.org/wiki/Position_sensitive_device"
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Ok, thanks.
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the modulation is performed in the analog domain by somebody else. I dont have a clear mind of what the process is, I can ask him if this is really important to my design.
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It is the light that is being modulated, so that you get modulated currents at the output of your sensor. The reference of the 154kHz modulation source is important, because the sensor processing needs to be synchronous with that source.
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Here is a piece of code I found on line which can transfer a clock into a sine/cosine wave ...
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This is just a very simple NCO.
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so, if the code works, instead of using NCO, I can transform a square wave into a sine wave right? as long as I get a 154Khz clock.
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I doubt the code will work for your application. The Altera NCO component is simple to use. You can also implement sinusoid tables using ROM. At this point, you are still trying to understand all the components in your system will fit together. So for now, just assume you will be using 'something' that creates sine and cosine samples inside the FPGA, and they will correspond to samples of a 154kHz sinusoid. The generic name for that 'something' is NCO (regardless of whether you use the NCO component from Altera).
You now need to determine how the light modulation will be synchronized to your signal processing system, so you can accurately measure the demodulated currents.
Cheers,
Dave
Honored Contributor
