I make USB lamps as a hobby, but I would like to sell them at some point.
They are basic parallel series of leds, each LED has its own resistor to bring it to around 20ma max current.
I use the chinese dc-dc 0.9-5v boost boards for the battery powered ones.
I use an epoxy potted micro usb socket, just the vbus and gnd soldered ( no negotiation ) for the usb powered ones.
I want to make the usb lamps as safe as I possibly can, to account for user error. I'm concerned about two things. 1. that someone will connect the lamp to very expensive laptop usb port and it could cause damage. 2. that someone will connect it to a knockoff usb charger which could overvolt it and cause a fire.
I already have a set of 500ma self healing fuses ( 1206 from china ), and some other THT ones at 400ma from the UK.
Any advice on how to proceed would be greatly appreciated. I did wonder if just connecting the usb 0.9-5v dc-dc board might do the trick as they already seem to contain fuses.
Thanks.