Freezing temperatures affecting floodlight Electronics

Hey guys I don’t have the specs of the flood lights that I have out behind my house, this is a generalized question.
My multi LED flood lights behind my house appear to be a little more dim than they are in the summer.
Do the freezing cold temperatures have that much of an effect on the electronic components that drive the LEDs that would cause the light to appear dimmer ??

Do they have battery packs?

No. 110 volt

The LEDs don’t care. I can’t speak to the electronics in the driver circuit, though.

No battery pack connected directly to 110 volt

I think Scallywag was referring to the driver circuit for the LED’s. The may be affected by the frigid temps and take a while to warm up or just not work at peak efficiency in those temps. I have a LED bulb in the back porch light that takes 10 minutes to get to max brightness when it’s below freezing.

Fluorescent flood lamps are dimmer in the cold. A lot dimmer.

Check to make sure “110V” is actually 110V, and that nothing else is on that circuit (heaters, etc.) that’d pull the voltage low.

> Do the freezing cold temperatures have that much of an effect on the electronic components that drive the LEDs

At cold temperatures:

- Electrolytic capacitors Equivalent Series Resistance (ESR) goes up (way up below freezing). As ESR increases, this is like having a resistor of higher value in series with your cap, so it will be much less effective. For example when the high voltage input cap (after the rectifiers) freezes it will no longer deliver smooth voltage so your light will flicker at twice mains frequency. If your lights do not flicker when warm, but flicker when cold, this is why.

- Ceramic capacitors with cheap dielectric (Z5U, Y5V) lose a lot of capacitance. If these are used instead of wide temperature range caps like X7R, depending on what they do in the circuit there may be consequences.

- Transistors generally don’t care, MOSFETs have lower ON-resistance when cold.

- The voltage reference in the driver which is used to set current will probably drift a little bit too

Most likely culprit is capacitors.

the esr of lytics rising with cold is the biggest issue.
most led fixtures use the cheapest ones that just barely do the job.
leaving no margin.
otoh the leds are more efficient cold.
after it runs a bit and reaches equilibrium none of this matters.
it might be dimmer at startup but slowly brightens as it warms up which may not be noticed.