Current Setup:
Currently there are 4 LEDs in parallel being powered from the 3.3V pin on the Nano 33 IOT with no resistors.
A lack of resistors seems wrong but the light is too dim for a desk lamp with a 330ohm resistor.
While this does work and the visible light produced is spot-on, the heat being generated by the LEDs suggests a new layout is required.
Currently there are 4 LEDs in parallel being powered from the 3.3V pin on the Nano 33 IOT with no resistors. A lack of resistors seems wrong
I understand, currently you use the Nano33IOT just for its Power Supply module, an MPM3610 which should deliver 3.3V x 1.2A. If the 4 LEDs are very similar and you wire them in parallel, each gets roughly 1/4 of the 1.2 A and so they might survive eventually, as they can bear 700 mA each. (However, as soon as one dies, this will kill the others)
Usually Power LEDs get a Constant Current Source (aka LED Driver) supply, rather than a resistor.
If you wire the LEDs in series instead of parallel, 12-14V / 350mA (=4..7W) (or more current, if you need it very bright) is fine.
BTW: The tiny heat sinks are the critical part in your design. How do you mount the bulbs on the aluminium plates and where/how do you mount those?
michael_x:
BTW: The tiny heat sinks are the critical part in your design. How do you mount the bulbs on the aluminium plates and where/how do you mount those?
The bulbs are soldered to the aluminum plates with a small amount of thermal paste applied. The aluminum plates with the LEDs are "floating" in the upper portion of the lamp and not touching anything.
The wires being used are stiff enough to hold all 4 plates w/ LEDs without resting on anything.