I'm back. It's been a year. I tried using many different resistors and diodes and had no luck, I gave up on it for other Summer projects.

Just recently I decided to revisit this project, so I tried out Grok (AI) to see if that could come up with a solution.

Grok suggests that I use a PNP transistor along with a 4.7kΩ resistor to get the motor to behave along with the LED: so that when the sun is out the LED is off and the motor is off as well, and the battery charges up.

This is the wiring diagram:

PCB (LED+) ────[Positive Wire]───[Emitter] PNP
│ │
│ [Collector]───[Motor+]───[Motor-]───[Negative Wire]─── PCB (Ground)
│ │
[LED+] [Base]───[4.7kΩ]───[S+ (Solar Panel Red Wire)]


I'm gonna buy a variety pack of transistors (I already have a variety of resistors now). And see if I can get this working. I'll report back at some point, either successful or up for another solution.

BTW the controller chip is now YX805, that's what they are using at the dollar store these days. I'm assuming it's very similar in function to what I started on in the beginning.

 

One other thought, as I go thru the thread. How much current does the motor require to run?? My guess is quite a bit more than the original LED required. AND, if there was a shorted circuit with the battery connected then it is possible that damage was done. That has already been mentioned, and I am just repeating it. It looks like there might be some wires bent over and touching on the solder side of the PCB.

 

How much current does the motor require to run?? My guess is quite a bit more than the original LED required.

My guess is also "quite a bit more than the original LED required."

Some of those LED solar lights use "Jewel Thief" circuitry to light the LED, meaning a 1.2V battery that normally couldn't light a 5mm LED that might take 20mA to light and boost the voltage and briefly light the LED. On and Off so quickly that your eye sees a continuous source of light. That's not going to run a motor no matter how many active or passive components you throw at it. Really, if it is as I suspect - and probably MisterBill2 as well, this is a non-starter project. 's not gonna work.

 

One more dumb question!! What is the motor intended to actually DO?? Running with no load is one thing, but generally a motor is used to provide action that somebody wants done. A motor running but not doing any work is a waste of energy.

 

Perhaps I missed it, but is this motor in any way a reasonable match for the board?

How much current did the LED draw?

What established that current? An series limiting resistor? Or does the control chip establish a constant current output of some kind?

How much current does the motor draw, but with no load and under the intended load?

 

One other thought, as I go thru the thread. How much current does the motor require to run?? My guess is quite a bit more than the original LED required. AND, if there was a shorted circuit with the battery connected then it is possible that damage was done. That has already been mentioned, and I am just repeating it. It looks like there might be some wires bent over and touching on the solder side of the PCB.

I don't know for sure if damage was done. Fortunately these attempts are only $1.25 each (buying the solar light from Dollar Tree).

That PCB image was from my first attempt. I've done my soldering a bit more cleanly since then.

 

My guess is also "quite a bit more than the original LED required."

Some of those LED solar lights use "Jewel Thief" circuitry to light the LED, meaning a 1.2V battery that normally couldn't light a 5mm LED that might take 20mA to light and boost the voltage and briefly light the LED. On and Off so quickly that your eye sees a continuous source of light. That's not going to run a motor no matter how many active or passive components you throw at it. Really, if it is as I suspect - and probably MisterBill2 as well, this is a non-starter project. 's not gonna work.

Yeah. I have no idea. I'm just a novice with limited tools to work with.

I've taken a solar light and then attached a tiny N20 motor in parallel with the LED and used a simple on/off switch as a proof of concept. This works fine, but it doesn't shut off in the sunlight, the motor prevents the solar panel mechanism that turns off the power to the LED when the sun comes out. But the motor runs and the LED lights up. I've run it in the sunlight a few times and tested it to work; meaning the motor doesn't burn out the LED or the circuit. It just doesn't turn off when the sun is out.

The motor I did this with was one of those tiny geared N20s that's rated for 3v-6v. (Here's a link to one: https://www.amazon.com/Coliao-Micro-Motor-Gearbox-Motors/dp/B0D93WTY3W)

The whole concept was to just make a neat little gadget that has a light and a little motor that causes an action like something you'd see in a fancy cuckoo clock (something that spins around). And it wouldn't last more than 20-30 minutes, it would trigger when the sun set.

 

One more dumb question!! What is the motor intended to actually DO?? Running with no load is one thing, but generally a motor is used to provide action that somebody wants done. A motor running but not doing any work is a waste of energy.

The whole concept was to just make a neat little gadget that has a light and a little N20 3v-6v motor that causes an action like something you'd see in a fancy cuckoo clock (something that spins around). And it wouldn't last more than 20-30 minutes, it would trigger when the sun set.

 

Perhaps I missed it, but is this motor in any way a reasonable match for the board?

How much current did the LED draw?

What established that current? An series limiting resistor? Or does the control chip establish a constant current output of some kind?

How much current does the motor draw, but with no load and under the intended load?

I am not sure, but I did a proof of concept with an N20 motor that's rated for DC 3v-6v. The motor still runs fine when wired in parallel with the LED light, it just vampires power when the sun is out (when the circuit is supposed to prevent anything from running to the solar panel will charge the battery). When the motor pulls that power, the LED also lights up.

So what I did was to find one of the solar lights that had an on/off switch. So I could turn this thing on and off. It charges up fine in the sunlight and when I flip it on, the motor and LED light run fine. It lasts for about 30-40 min. I've done it several times so the motor and the circuits and the LED don't seem to be damaged.

I just wanted to get the motor to shut off along with the LED when sunlight hits the solar panel (just as it's supposed to if it was just running the LED).

I'm a novice with this stuff and I don't really have anything but a simple multi-meter and soldering iron. I was hoping someone else would have done something I could just copy from, but I'm having to brute force this thing with my limited knowledge of circuits.

 

Sun up - - - no LED
Sun down - - - LED

New arrangement:
Motor attached - LED ON, motor running.
Switch it off - - - battery charges?

Thought the purpose was to have the motor come on automatically when the sun sets. Does the lamp still work as originally designed? Does the LED com on at night and does the battery charge during the day?

 

The question seems to be "What is different with the motor from the LED?? How about trying a 0.1 MFD cap across the motor? The issue might be motor noise making something reset.

 

The difference is that the motor will run on 1.2V (the battery voltage) whereas the LED will not, because it requires about 3V.

I suspect the battery voltage is always applied across the LED. In sunlight, the LED does not light because that voltage is too low. But the motor will run on that voltage.

Here is how you can test that theory:

Take a good operating solar light (no motor) and measure the voltage across the LED when it is in sunlight. If I am right, the LED will be off and the voltage will be about 1.2V.

 

Sun up - - - no LED
Sun down - - - LED

New arrangement:
Motor attached - LED ON, motor running.
Switch it off - - - battery charges?

Thought the purpose was to have the motor come on automatically when the sun sets. Does the lamp still work as originally designed? Does the LED com on at night and does the battery charge during the day?

Well, when I couldn't get the motor + LED configuration to obey the sun up=off and sun down=on routine that the circuit is normally intended to do, I decided just to see if I could get the motor + LED to work while using a solar light configured with an on/off switch. Just to see how long the motor would last with the LED running.

I had this little project where I made a garden decoration, and I wanted the motor to spin this carousel thing to imitate one of those fancy cuckoo clock with the characters. I just resorted to the on/off switch because I couldn't figure out a way to get the whole thing to turn off with the sun out. So flipping it on and off worked for the purpose of proving the motor + LED can run (albeit for just 20-30 min). When I flipped it off, the solar panel would charge the battery and then it was just a matter of flipping it on again if you wanted to see the carousel turn round and round (similar to the concept in the clock shown below). My hope is to figure out how to get the motor and LED working so that it will obey the circuit's sun up=off and sun down=on routine.

 

The difference is that the motor will run on 1.2V (the battery voltage) whereas the LED will not, because it requires about 3V.

I suspect the battery voltage is always applied across the LED. In sunlight, the LED does not light because that voltage is too low. But the motor will run on that voltage.

Here is how you can test that theory:

Take a good operating solar light (no motor) and measure the voltage across the LED when it is in sunlight. If I am right, the LED will be off and the voltage will be about 1.2V.

I will try this out. Thank you.

 

The question seems to be "What is different with the motor from the LED?? How about trying a 0.1 MFD cap across the motor? The issue might be motor noise making something reset.

I will see if I can find an MFD cap. Thank you for the suggestion.