UVC Lamp causes Atmega 328P to malfunction

Question

I have got an Atmega328p which connected to a TFT LCD 1.3 inch using SPI. The Atmega 328P is powered through a 5V adaptor. The problem is most of the time when I switched on the UVC Lamp the LCD will stop working and sometimes the Atmega328p also stops working. Even when I connect the UVC lamp directly to the power line, and did not connect it at all to the Atmega328p it still causes malfunction. I have tried adding 680uF capacitor to Atmega 5V and GND but it seems to not solve the problem either. Does anyone know why this happens? And what steps should I take to solve this?
Here is my Schematics:

I connect the UVC lamp separately and directly to the power lines.
This is the UVC Lamp that I use, I can't seem to find any datasheet for this:

Yamano UVC Lamp Germicidal

Andrew Lentvorski · Accepted Answer

While lots of folks are hypothesizing EMI, I would personally suspect that it is the photon flux from the lamp.  A UV germicidal lamp has pretty energetic photons with a pretty solid photon flux.  If you have some chip that isn't sufficiently opaque to the frequency of light emitted, you can get some weird effects.
For example: Xenon flash bulbs could reboot a Raspberry Pi 2 because they would generate carriers in the silicon and flood out the transistors in a power regulator chip.
https://www.alphr.com/raspberry-pi-2/1000375/why-a-camera-flash-will-reboot-your-raspberry-pi-2/
That lamp looks like an actual commercial product for aquariums, so I'm making a big assumption that it had to pass radiated emissions testing somewhere other than China.  Thus, I'm kind of skeptical that it is radiating enough to set off an EMI-caused reboot.
Good luck.

UVC Lamp causes Atmega 328P to malfunction

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