So when I found the QX5252 (and bought 100 of them), I thought I had my answer. 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. These only last a short time, specifically without using a solar cell, and a 330 uH inductor A standard (toroid coil style) Joule Thief light will just keep draining, and go for days and give me plenty of light. Specifically because the low V cutoff kicks in and turns it off. 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. 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. 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. 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 need about 100 of them, and it's got to be cheap, easy to make, and low maintenance. I'm looking at building some small lights for recycling stations at a festival that goes on for around a week. Here's the back story about what/why I'm doing if you're curious.
#5252f solar light how to#
I'm not using rechargeables, but rather old "dead" AAs.Īny 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. 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.īut I've run into one quandary, and wondered if any of you knew a way around it.Īs 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.īut 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 used a power supply to run the PIR sensor module because it needed 3.5 volts to work at all.
#5252f solar light driver#
I kept the LED driver voltage to one battery and did not need any resistance from the battery to the transistor The LED's will come on with movement, but since the photocell is facing straight up, my shadow was enough
The CDS voltage becomes the only thing deciding if the LED driver should run or stay off. I tested the high signal circuit by sending 2.5 volts to the PNP transistor to turn it off with a PIR motion sensor module. A 10 uF capacitor will delay the turn on time! The CDS control and Pin 1 capacitor are optional for various requirements. The setup also allows higher voltage signals to be sent just by turning the transistors off. Here is what I came up with to control the 5252F chip while using a photocell to only light the LED's at night or in a dark room:Įach transistor setup conducts when the signal is not present to supply battery voltage to Pin 1 even if the CDS voltage is low.