Clint Jay left a comment on the Poundland GU10 lamp video saying that it glowed on just 12V. I tried it, and it does glow!
Then I tried it on lots of other GU10 LED lamps and just under half of them glowed, with one actually running at a full watt of power!
The ones that didn’t work probably contain a variant of the BP3102 style chip that has a built in power supply circuit that only kick-starts at a modestly high voltage, so that probably prevents them from starting on 12V. The others tend to have more discrete circuitry that is capable of running on quite low voltages.
One lamp started quite brightly on 12V but then went out, but still drew a lot of current suggesting that its circuitry had possibly locked up.
A few of the lamps actually put out useful amounts of light at 12V, so they could theoretically be used as deliberately low level lighting with a 12V battery in the event of a long term power outage. (That should thrill the preppers.)
