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It Lives! 8-Bit CCD Driver Circuit TCD1304DG...

A project log for DAV5 V3.01 Raman Spectrometer

The only thing worth doing, is the thing worth doing right!

david-h-haffner-srDavid H Haffner Sr 07/13/2017 at 15:440 Comments

*UPDATE* 07/15/2017 @ 3:14:PM

New updated schematic (8-Bit CCD driver circuit)

It was brought to my attention today that there may be some signaling and grounding problems with this design and PCB, well I cannot see them, please if anyone else can see a problem here as compared to the 4 spectral images I have posted in the last 2 days, let me know.

It was stated that I should start all over again?

Early this morning I fitted my entrance slit with a #3 variable adjusting Polarizing filter (30 mm diameter,) which I can turn from 0 deg to 360 deg open or closed depending on how much light I want to enter.

These two spectral images are the results from those tests this morning:

I used another CFL lamp with the same rating as the overhead lamp from before, only this one is portable, and as you can see from the data description it is only 8 cm from the slit, but now I can adjust the polarizing lens to let only a certain amount of light through.

Keep in mind now, that the spectral image is is not bounced off of any diffraction grating, just straight through the monochromator, this is just fine though because the slit is only 2 mm in length and a width of only 0.1mm, so the peaks are sharp and well defined.

The SNR (signal to noise ratio is well within the expected range I thought it should be in,) I will be making another post soon explaining how the SNR works and how to calculate it, it is crucial, and you need to know it :)

This spectral image was taken with a factor of 075 deg aperture opening.

The next spectral image panel has an aperture opening of 025 degrees;

UPDATE#2 I uploaded the fixed gerber files for PCB manufacturing.

UPDATE: I almost forgot to tell everyone, the spectral images are inverted but not to worry, this is the formula that will turn it right side up:

(10ᶺ(-B2))*100

The "-B2" is just the cell# in the second column in Excel, you would input this in that cell# and copy it down the entire path of data in that column, and it will transform the inversion to Transmission data.

Well, it..is...ALIVE! I had to de-construct the PCB files, I made a terrible mistake that was costly, so I rebuilt the circuit on my breadboard and she runs beautifully :) I have fixed all the gerber files and will upload the updates. 1st things 1st...here are the first test spectra using a CFL lamp at 7.5ft (228.59cm) overhead room lamp:

This is the 1st test using an integration time of 0.250 sec

This is the 2nd test using an integration time of 0.5 sec

The next set if images are of the circuit build on the protoboard:

I will be uploading the PCB gerber files which are all updated and fixed up, the board dimensions are: 88.99 X 80.01 mm

Here is the updated and fixed schematic:

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