This was a gift I gave my parents some years ago. After my dad passed away in 2012 I got it back. After replacing the Rechargeable battery in 12' it has been out in the Center of my pond at my Cabin. Last time there I seen it wasn't working right and thought it only needed a LEd or 2 replaced. So Today while there I Detached the top and brought it home so I could give it some fresh paint and replace the LEDs. While only 2 where broke at the hat as I was removing them a couple of the others just snapped with very little pressure so had already planned to replace them all..

However thought I would mention that there was some heavy damage to this PCB with signs of water damage. Growing corrosion around most Voltage traces. After doing some minor cleaning I installed all the LEDS back into the PCB and it did work as it should have besides one LED. this was do to bad trace.. So I made a jumper to test that it was working as it should. However do to the damage of the rest of the PCB I took all the LEDS and Header pins out of the board only leaving the few SMD parts and the mound with hidden chip. The header pins connect to a different PCB with Solar controller and other items. that board is without damage.

Trying to clean this off without to much damage proved to be harder and the corrosion had eaten some other traces right up to the Hidden chip dome. I do have a 2032 for my Hakko FX-951 and have some small micro tips. My main issue is I don't know really how some of the tracks were laid. There is one on the right side of the hidden chip mound that looks like it may have been coupled with one trace that split into 2 others one going to the chip before a Resistor and one after the resistor.

Anyone have an idea what Chip may be under this mound so I can try and find a data sheet on it so I can repair this PCB? I know posting a picture of front and back of PCB would help much. However I thought maybe someone might see how this is laid out and may have dealt with a chip on this type of setup

I would be willing to design another PCB that I could use in this place if I needed to. I just don't know what type of chip would work with 6 LEDs on a 1.2v. I did hook up a PSU and gave this setup 1.5 to 1.8v to see what the current draw was and was no more then 40ma. Without the LED PCB plugged in the draw was 18ma. Over 2v the main PCB went into protection so it does have a Over voltage protection on the main PCB.

Because of where I have this Lighthouse placed on my Pond, I would like to try and design something that would be able to run off the Solar system and a 1.2v AA.

James

 

you can use the qx5252 I sell these and also others have such IC for low cost.

If you need more than one LED you can use several IC or use a larger LED with more current.

Theres SMD 0.1W for instance

 

Thank you, That don't really help. I am looking for something that would be like a Timer or something like that. I guess to understand better. This PCB has 6 LEDs, One turns on as the one before it turns off to give the effect of the lighthouse light rotating. If I wanted static lights. I already have a Solar controller that also outputs to the upper PCB that has this hidden chip. This PCB pictures above has 6 header pins that are 3+ and 3- where I could just plug in 3 Leds. That don't give the effect that I am looking for. What ever it is under that mound does a rotation that comes out to the ground pins of the LEDS...

So I know I could do something with 555 and 4017, However that isn't what I am looking for because I would have to redesign something for higher voltage and I would like to keep everything installed within the Lighthouse top and keep it with the small solar panel that this unit already has. It has been tested and still in working order.

 

You might wish to look at Wingsy's Lighthouse project, Pro
jects, several days ago. Same effect but with 16,? , LEDs using PWM.
You may never know what was under the black dot. Might have to re design a new circuit
which still could use a single AA .

 

So while working with this some more. I did some testing of the Solar controller board and also tested the output at the header to see what the voltage was there. With a AA 1.5v doing just over this as I put in the battery holder it came out to just over 5v at 5.05v. It has now being powering a 555 and 4017 Circuit that I built as a backup of I can't find what I am looking for. Sadly this don't power the lights to well at such a low power in put. It has been running so far for over 7 hours. This circuit I tested it to make sure it could run low voltage and runs ok just very dim.

So damage to the old Rechargeable battery has been done. so when I replace this one it will have even lower power then this 1.5v normal battery. So I know this 555 and 4017 is really not a good solution. It would work and give the effect at the light house. What was nice is that it had enough power on the old setup to reflect some off the pond. As low power this 555 set up is I am sure there will be no reflections..

I am going to try and drill out some of the mound off the traces where they enter with hope they are not damaged enough to make some jumpers. Only thing I don't understand is there is a spot that looks like it entered the chip came back out though a resistor and back into the chip. However the traces are so tight together and does look like they may have been traces that used this hole as a splice to split between 2 areas one going though the resistor before entering. It is just a little confusing. Never looked over this board before there was damage so I don't know what goes where or how in that one area. Everything else I can easy follow. The area I am talking about in the photo is between 1R1 and the black mound there is a hole that goes no where on the other side.

I will see what I can do. Already have the transformer wire cut and ready for running jumpers. Even this is little larger then I want to use I could always use strand from solder wick but I think that is to fine and not coated so no good around the bare traces not sure why one side they covered and other side they left bare..

 

Well I did some more looking and started make the repair to this. Changed out a 0603 Resistor for a 0805 seeing it was a good fit. Added my first jumper on the one I thought was the hardest of the easy traces to repair. What is the worse that can happen. I do all this repair and I still need to redesign this PCB and build my own. There are some areas that I won't be able to do trace repair however I will be able to go from device to device on them traces and seem will be an easy repair in the end. Most times I do repairs with longer wires so these small area trace repair is kind of a pain for my not so young eyes and hands. Will do my best to make this repair and will paint this with solder mask paint. All after doing some testing on the repair if checks out I will Ultrasonic it in some Branson EC, then do the paint coating.

 

Update on this, It isn't 100% like it used to be, however I am happy enough with the Repair that I am doing a test right now with a New battery

Problem is that for what ever reason the 2 LED's closest to the Chip stay on for whole rotation. Now there is some change in brightness when it does get to the LED in the rotation. This was one of the LEDs that wasn't working because of the blown trance on the PCB. With how tight the area is to work in there I elected to run some trace jumpers on the other side a total of 3 on each side.

It is kind of hard to take pictures and show working LEDS lol however in the 3 photos you can see in 1 picture there is 2 leds that are lit one brighter then the other because it does give a rotation effect and was able to get that in a photo. another pictures shows 1 lit in another area and so on. Seeing I don't get up to the cabin as much these days I think I will have some time to work on a new setup to replace this one at some time. Until then this will work. Might even design a couple that I can run with different functions. One like this with rotation look, One that I could change out for a beacon look and maybe even one on a motor that rotates a light.

Give me something to do on days I don't have anything lol.. Thank you for the ideas..

James

 

The blob is a glop-top COB. See https://en.wikipedia.org/wiki/Electronic_packaging

So, it's effectively the die of an IC, probably wire bonded to nearby pads and covered in a glob.

 

Any guess as what the LED current is & what is the rotation rate ?

 

Not sure of the Rate. However it seems the current is around 20mA. I am not 100% sure on that however while using a Power supply to work with it at first. I did see it went from 17 to 20mA without the LEDs in the Header to 37-40mA while installed. So that is my reason with the numbers.

The speed is kind of a high rate. Not something to fast, I might even be able to replace the Resistor to change that rate however I am not sure I want to mess with things at this stage because it is working for now. I did replace the Resistors that were installed with new ones of same value just updated the size even though I have both sizes. It just looked to small on the board like they didn't have the right size to start with.