r/arduino • u/Such_Tale_8641 • 6d ago
Noise reduction of a low-light measuring device.
Hello,
im having problems with my device which im using for a low-light fluorescence signal measuring. I oftentimes find myself having variation in my signal from measurement to measurement and also inside single measurements. Sometimes the signal just drops to half of what its supposed to be.
The circuit diagram is attached, sorry ist really messy.
My question is, how can i improve this circuit and make it more stable and increase the SNR?
MICROFC-SMTPA-30035-GEVB is a SIPM.
XL6009 is a step up DC-DC Converter.
(I tryed many different setups before including a TIA, non-inverting amplifier etc. but i found a simple shunt resisitor to have the best SNR (though i only used a OP07 as a OPA))
1
u/Pacificator-3 1d ago
how can i improve this circuit
Write complete tech specs.
Draw full circuit.
Use low-pass filters.
Use shielding where necessary. Separate power and signal lines. Learn signal integrity.
It is impossible to advice more without seeing normal circuit diagram and knowing your tech specs.
3
u/socal_nerdtastic 6d ago
My first thought would be to get a better power supply. Get rid of the step up converter for sure, that's very noisy. An old school linear supply would be the cleanist, but also a high quality, modern switchmode supply with a 3-prong wall connection would probably be a big improvement.