In this project, I continued working with the TCD1304 linear CCD. I created this PCB to fit on the back side of a B&W TEK BRC100 OEM spectrometer. I managed to buy the optical parts of the above-mentioned spectrometer without the CCD, so I created my own circuit for the CCD.

The PCB design is very simple, I used a 4.096 V voltage reference to supply the CCD and I used an OP-AMP, to invert the output signal of the CCD. The inversion was necessary in my opinion because originally, the CCD outputs the signal in a way where the darker pixels give a higher output signal. For me, this was a bit confusing because, in my mind, the output signal should be directly proportional to the amount of light reaching the CCD. Therefore, the more light enters the CCD, the higher the signal should be. I picked the resistors in a way that the signal of the overexposured pixels nearly saturate the ADC of the microcontroller.

Of course, the PCB is not only suitable for this specific spectrometer. With this miniaturization, it is easier to mount it on different things and with the help of the wires, the microcontroller driving the CCD can be placed somewhere else. However, I should mention, that you should avoid using too long wires in order to preserve good signals and avoid noise. To potentially decrease noise, I wrapped one of the ground wires around the output wire (OS) in my application.

I should also mention that this matte black PCB is perfect for this application because it helps to avoid unnecessary reflections. I really recommend picking this colour!

I attached an interactive BOM file, so it is easier to see which part goes where.

For further information and a video about the project, please check the links below.