I am working on a Power Supply for LEDs. It's a single Power supply that multiplexes 6 PCBs LEDs. The Power Supply it's working fine, I can succesfully dimmer the power of the LEDs, even 100% duty cycle. But the issue I am experiencing is that when one of the LEDs is on, there is a lot of noise spread all over the board.
At first I thought that the source of the noise was the switching between leds, but if I keep only one LED turned on, I still get a lot of noise.
The following images is oscilloscope images, the cyan is the diode anode/dreno/inductor node(D13,Q11,L2) and the dark blue is an GND measured and two different point the PCBs. Another fact is everytime I turn on the LED I lost communication with UART devices and with the STM32 debugger.