So I have a particle Photon that I’ve been using to interface with a PLC. It has been working fine so far, code is being flashed successfully and it is sending data up to the Particle cloud. However, the Photon only works when it is being powered through the microUSB port so if I want to run it at all I need to have it connected to a computer or some other type of 5v USB source.
This won’t work as I want to run it off of the 24V power supply inside of the PLC cabinet. But when I connect it to the power supply (through a 5v L7805CV regulator) to the VIN pin, it works normally for a few seconds - going through setup and eventually breathing cyan to indicate that it’s connected to the cloud - and then suddenly starts flashing the white LED and the D7 LED rapidly.
I’ve tried switching out the 5v regulator with a 3.3v (LD33V) regulator, I’ve tried using the 3.3v regulator to power it though the 3.3v pin, and I’ve tried using the 24V source from the cabinet and a benchtop power supply as the input to the regulators and each time the result has been the same.
However, when I connect the photon directly to my benchtop power supply set at 4v, it works fine.
Why is this happening? I’d rather use a voltage regulator to supply the photon instead of a DC-DC converter or something as it’s less hassle and takes up less space. Am I doing something wrong?