Some others probably noticed, filament LED has made its way into low-voltage solar garden lighting. One difference: low-voltage/high-current parallel LEDS (or low-current given its low brightness), compared to line-powered which is high-voltage/low-current series connection.
I opened the light and found nothing unusual: PCB with COB driver chip with inductor and diode, no indication of voltage boosting for series LED drive. I probed LED and measured only 2.5v dc but this is averaged if it being pulsed (very likely); nothing further at the moment.
This makes me wonder about the economics of filament v. single LED in this application. Filament light sells for $4 but beyond fancier plastic, is not much different from basic light which costs $1.25 . Light output was good but did not last nearly overnight, maybe due to 2/3 AA battery rated 100mAh, one of the smallest available.
As it turns out the filament solar lamp mentioned above looks good, but held up for less the two hours despite being in good sunlight for several hours during the day. It also came on too early i.e. with too much ambient light. Not a good design.
Ikea now sells a new small filament bulb: E12, 2700K, 15k hours, 100 lumens, 0.9W (111 lumens per watt). Perfectly good
for lighting small areas at low intensity. Not dimmable but at this level no real need to. Other sub-1W bulbs exist but not
many with this efficacy. 2700K is OK for me although Ikea tends to go down to 2200K with this type of bulb.
Not sure what the bulb size designation is but it's somewhat similar to appliance bulb, approx 4.5cm diameter.
Just or fun I tried it as a porch light; not very bright but I can claim to have broken the 1W barrier.
I found 110v ac LED filament bulbs, 60W equivalent (7W)in A15 i.e. appliance bulb size, in clear and
frosted. May not be absolutely new but just noticed them. Not thrilled by the 10k hour life on these
particular ones but price was not too bad so trying a few out. They should at least pay
for themselves. (**)
Light dispersion is much more uniform than older bulbs with planar SMT LEDs. The glass bulb gets
quite uniformly warm, unlike classic bulbs with metal collar; heat flow mechanism and paths
are obviously different. Frosted version is difficult to distinguish from a similar incandescent bulb.
Dave
** even compared to similar bulb consuming 9W, will save $4.40 over 10k hours
based on average $0.22/kWh here. Bulbs were $2.83 each including tax.
Re: Next generation Filament LED
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