Soldering Circuit Board on Christmas Fairy Lights to stop annoying blinking

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Marvinmuffintan

Joined Jan 27, 2021
1
Hi everyone, im an absolute beginner here and i was made aware that i could technically solder some parts of a circuit board together to achieve a consistent steady light on my christmas fairy lights, which currently need to cycle 7 modes before it gets to a steady mode. The issue is that i have connected them to a smart plug timer which turns it on at a pre defined time, so its annoying to have to manually cycle the modes 7 times to reach the steady light every single day, and defeats the purpose of a smart timer if i am at the switch manually cycling the flashing modes as well.

Im hoping someone on this forum could advise me on what points to solder together for each circuit board, to by pass the flicker and reach a steady light output every time. Thank you in advance!
 

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ApacheKid

Joined Jan 12, 2015
385
Do you just want to eliminate the modes altogether? just have the light either fully on 100% or fully off and no other options?

Also what is the odd looking object we see from above - in the picture of Circuit board B? from the underside we see a few strips near it but its very odd looking, is it another board soldered on sideways?
 

wayneh

Joined Sep 9, 2010
17,152
Hi everyone, im an absolute beginner here and i was made aware that i could technically solder some parts of a circuit board together to achieve a consistent steady light on my christmas fairy lights, which currently need to cycle 7 modes before it gets to a steady mode. The issue is that i have connected them to a smart plug timer which turns it on at a pre defined time, so its annoying to have to manually cycle the modes 7 times to reach the steady light every single day, and defeats the purpose of a smart timer if i am at the switch manually cycling the flashing modes as well.

Im hoping someone on this forum could advise me on what points to solder together for each circuit board, to by pass the flicker and reach a steady light output every time. Thank you in advance!
See all those wires that go out to the LEDs? They provide individual control to a subset of the LEDs. The controller powers up those individual strings in a pattern as pre-programmed in the controller. It looks to me that there is a +bus and a -bus on the outer two pins, and the inner 4 are switched by the 4 transistors.

You need to probe those pins with a voltmeter to see what's happening. You could even use an LED with a current-limiting resistor to indicate on or off. Once you know which is which, you'll probably end up moving the inner 4 conductors onto the appropriate bus pin, and this will effectively bypass the controller.
 

Tonyr1084

Joined Sep 24, 2015
5,969
From what I THINK I can tell, the COB (Chip On Board) controls four MOSFETs. Or something like that. Each FET is a switch providing a pathway from the LED's to the "Negative" control. Pos (positive) is common to all lights ( I THINK! ). This is just a guess, but if you solder a jumper between the three negatives together (blue line) and you jump the source and drain leads of the FET's (blue line) you should have all the lights on constantly.
1612803689689.png
 

wayneh

Joined Sep 9, 2010
17,152
Thanks to @Tonyr1084, be reminded that there is line power on the board and that means you need to be very careful of that. If you power it up while probing for voltages, be careful and assume every pin is hot until you prove otherwise. Don't move any leads around until you're sure. Label any lead you plan to disconnect. They'll all look alike later.
 
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