I bought several LED bulbs about 2 years ago, and now before turn LEDs steady on, some of them flash for some time. Frequency of flashing may differ from bulb to bulb. After some time flashing, they turn LEDs steady.
Here's the device it (supposed) to use: BP2832, but datasheet shows BP2832A chip, while my bulbs use chip without A code.
Interestingly, I opened one of bulbs, and drew its circuit diagram, and it differs with datasheet. I hardly believe that adding A code will change pin assignment, and think there's mistake in datasheet. Edit: datasheet in Chinese language shows correct pin assignment!
So here's the actual circuit:
(sorry for childish drawing, I want to show differences with typical circuit shown in datasheet). "+" means two resistors in series, "|" means two resistors in parallel.
Here's the board from both sides:
Nothing really damaged, the only green plastic coating torn off one of the capacitors, and big resistors (15R+15R) become kind of grayish because of heating of the bulb.
If you came across this "blinking" issue, or even had been dealing with this buck LED driver, please share what do you think is the cause of issue and what is possible order of replacement.
Update: here're caps
400 V caps are 105 degrees C rated, 50 V is 125 C rated. As Spehro reasonably noticed, I did mistake in 50 V cap value - it is 22 uF.
I do not have equipment to measure capacitance or ESR, I will just look for replacement.
To be continued...
Update: Here's the follow up question with the bulb redesign.