sadesh wrote:That was great invention of solar LED. congrats,
holtt wrote:Hi, glad I found this thread! I've been messing with the QX5252 the last week, making a nice little minimal Joule Thief-like setup.
But I've run into one quandary, and wondered if any of you knew a way around it.
As mentioned before, the chip will turn off the light when the voltage gets below 0.9 or so, to prevent over-discharge of a rechargeable battery.
But in my specific application, I'd like it to just keep going - to NOT shut down, but instead just drain the battery to nothing. I'm not using rechargeables, but rather old "dead" AAs.
Any thoughts on how to bypass or disable this feature? I actually want it to drain an old AA down to as low as it goes, and I don't care if it gets kind of dim after a while.
Here's the back story about what/why I'm doing if you're curious...
I'm looking at building some small lights for recycling stations at a festival that goes on for around a week. I need about 100 of them, and it's got to be cheap, easy to make, and low maintenance.
My thought was to use a Joule Thief circuit, and use "dead" AA batteries to run it all - which would really be in the spirit of recycling and all that. I could load them up with "dead" AAs (i can get hundreds at work), then just keep an eye on them during the festival and swap out the ones that finally go out. I'm used to toroid-style Joule Thief circuits running for a week just fine, so I know this doesn't have to happen often.
The problem is, when I use "dead" AA batteries with the QX5252, I only get about a day's worth of light out of them with this chip. Specifically because the low V cutoff kicks in and turns it off. A standard (toroid coil style) Joule Thief light will just keep draining, and go for days and give me plenty of light. These only last a short time, specifically without using a solar cell, and a 330 uH inductor
I could just make the standard coil type, but since I need around 100 of them., that's a lot of toroid coils to wind. So when I found the QX5252 (and bought 100 of them), I thought I had my answer. Very easy to make with out much fuss. And dirt cheap as well.
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