15 white LEDs are connected in series, with an operating voltage of 120V. Have you ever seen such LEDs?

tagetage

15 white LEDs are connected in series, with an operating voltage of 120V. Have you ever seen such LEDs? [Copy link]

 

In the previous post, I disassembled an LED bulb. The main purpose was to see if the LED was driven by a constant current and whether there was PWM dimming when the LED was working.

I measured the voltage of these 15 LEDs in series and it was as high as 120V. The voltage difference of each LED was 8V. Have you ever seen such LEDs? ?

LED lamp disassembly, do you think this circuit is driven by constant current?

https://bbs.eeworld.com.cn/thread-1285215-1-1.html

wangerxian

So if I string fewer or more strings, will it work properly?

tagetage

wangerxian posted on 2024-6-20 21:40 If I string a few less or more, will it work properly?

It should work, I'll test it in my next post.

不亦心

The imitation tungsten filament lamps and retro LED filaments that were popular a few years ago were tens of volts or even hundreds of volts.

吾妻思萌

That's awesome! If one of these breaks down, won't the whole thing collapse?

wangerxian

tagetage posted on 2024-6-20 22:03 It should be possible. I will test it in my next post.

Be careful, the voltage is quite high.

dcexpert

There are more and more high-voltage LEDs now.

TH2018

Some lamp beads are 9V, which integrates 3 3V lamp beads.

damiaa

Everyone has one at home, but it's not 8v.

tagetage

Azuma Simeng posted on 2024-6-21 06:38 Awesome, if one of these breaks, won’t the whole thing collapse?

Yes, they are connected in series, so if one is broken, all of them will not light up.

tagetage

TH2018 posted on 2024-6-21 08:50 Some lamp beads are 9V, which integrates 3 3V lamp beads

I suspect it is this type, with 3 LEDs enclosed in one package.

tagetage

wangerxian posted on 2024-6-21 07:47 Be careful, the voltage is still quite high.

Yes, because it is a non-isolated LED driver, I dare not try it.

tagetage

damiaa posted on 2024-6-21 09:38 Everyone has one at home, but it is not 8v.

Yes, I have 3.X volt ones at home, but this is the first time I have seen 8 volt ones.

tagetage

Bu Yixin published on 2024-6-21 00:31 The imitation tungsten filament lamps that were popular a few years ago and the retro LED filaments are tens of volts, or even hundreds of volts

I really don't know about this, I'll check it out later.

tagetage

dcexpert posted on 2024-6-21 08:20 Nowadays, there are more and more high-voltage LEDs.

This is the first time I have seen a high voltage LED. Although this bulb is new and has never been used, I learned a lot from it.

dcexpert

tagetage posted on 2024-6-21 09:52 This is the first time I have seen a high-voltage LED. Although this bulb is new and has never been used, I have learned a lot from it. It was not in vain.

High-voltage LEDs can simplify power drive and reduce power costs. They consist of multiple lamp beads connected in series.

se7ens

I agree with the 8th post. A high voltage LED may contain several LED dies connected in series and then packaged into one LED. When using it, you should pay attention to the fact that its heat generation may be several times higher than that of a low voltage LED with the same package. Therefore, reducing the operating current can ensure long-term use.

tagetage

se7ens posted on 2024-6-21 16:18 I agree with the 8th floor. High-voltage LEDs may contain several LED dies connected in series and then packaged into one LED. When using them, you should pay attention to the heat they generate...

You are absolutely right. When my LED is working, the aluminum substrate underneath is very hot, and I can't even put my hand on it. It feels at least 70 degrees.

吾妻思萌

After a long time, the whiteboard will turn black.