This chip can put out over 3700 lumens at its rated maximum which is more then two 100W lightbulbs, i think it would make a very excellent lamp.
12V and 2.4A is a rather convenient power requirement so could we invent a DIY kit to make such a lamp, a purchasable (certified) power supply, a heat sink, a fan (if needed) and circuitry for modes (why not) and to cut the power if the fan (if included) fails. Also a base to hold everything.
Your thoughts?
I don’t know where one can buy this chip right now, but i assume in a few months everyone will have them.
Theoretical parts list:
XHP70 chip
Power supply
Heatsink
Fan
Circuitry
Host
I’d like to avoid Fan if anyhow possible. If good enough heatsink is used it should be possible. Or somehow thermally integrate/connect the heatsink with the floor lamp body so that it also dissipates heat. There’s a ton of cheap CPU heatsingks, but would need some testing to see what is the required and available *C/W rating.
Also, ading a thermistor to provide the MCU with Temperature could be used to cut (down) the power if it overheats.
I am thinking about a home lighting project for a while now, and I could potentially contribute some hours (if wife allows of course :).
Mind that 12V halogens usually run on alternate current, you will have to rectify that (easy), and then get rid of the massive ripple (difficult, for 2.5A you already need big caps) or you will see a 50Hz flicker.
The XHP70 is available at DigiKey now too, as well as Mouser. But so far only the one power/tint bin is coming out. They list a lot of options, but I haven’t seem a time frame for when the others will appear.
This does sound interesting. The halogen floor lamp we have has a diffuse glass lens over it which would be perfect for this application. And yeah, it burns 300W and makes loads of heat!
Cooling fan below a drilled aluminum heat sink could be used to blow heat up and out, a small pcu fan would suffice and there are some very silent running ones these days.
I’ve been thinking of making DIY floor lamps recently. Cheapy floor lamps have made me unhappy recently.
That said, if it’s aiming straight up it probably needs more lumens.
Also, just to be clear, the basic premise for this idea almost certainly makes it incompatible with conventional wall and remote dimmers. Only LED/ DC PWM dimmers need apply.
A CPU heatsink with a copper PCB would work really well with an XHP70. Active fan cooling would be optional, but most CPU fans, when wired in series with a current limiting resistor, are whisper quiet. So it wouldn’t be too intrusive.
If you don’t need regulated CC, a 12V 3-3.5A laptop power supply would work really well.
i hope to have understood well what an floor lamp mean. here is my idea of building one. its all passive with no ventilator but an led mount on pc heatsink
building te lamp from scratch is a lot of manufacturing and design work, don’t think it is worthwhile considering the price of lamps in shops and man hour costs. I was more looking in the direction of converting an existing lamp to LED.
The idea with the “tube” to channel air is nice, but that’d require some manufacturing.
yes thats the main path from the heat but some help with air that flow will help too. since the idea was to drive hard those powerful leds to light an room.
this:
inside a tube seems easy and doable to me.
Convection will not work in a long thin tube like that. Air will not move. The air gets “stuck” in a thin tube like that, even w/ temperature difference (delta)!
This is the way to do it: lots of surface area and thermal mass.
Cheap floor lamps are bad. If you want to convert a bad cheap lamp to LED, buy a cheap LED bulb.
I think that with a little consideration a decent DIY floor lamp host can be constructed. Metal electrical conduit can be threaded on both ends for the base and head assembly. This forms a sturdier shaft than conventional cheap floor lamps. I’d like to hear some suggestions on good base materials, but I think there are plenty. The top can be fitted with a conventional lamp shade holder (probably the ‘under’ kind of holder). The shade will hide any potentially ugly LED head assembly.
Conduit and lamp shade can be sourced locally. Possibly the base as well.
Black spray paint will increase the emissivity of the conduite and make it look better. I’m not sure if the emissivity increase will balance out the loss of conduction with the air, but it’s basically required for aesthetics.
The problem with all of these propositions is that they are putting most of the light upwards, not outwards. Upwards emitting floor lamps need/should have ~5000 lumens AFAIK, and getting 5000 lumens out of the XHP70 will require a high current regulated source and very good heatsinking. In fact, thermal throttling will definitely be needed in that scenario IMO.
i hope to have understood well what an floor lamp mean. here is my idea of building one. its all passive with no ventilator but an led mount on pc heatsink