Interchanging backlights.

[unimatrix93]

Hey guys!

I have a LG TV with very dim blueish colored backlight.

I have 3 rows of LED strips, with 8 LEDs on each. 2.8V each of them.

Can I change the whole rows with another backlight strip from a Samsung TV?

The LED's voltage is the same, only difference is that there are 9 LEDs on each row instead of 8.

Could the PSU handle it or should I take of 1 LED on each row to match the voltage of the original rows?

Thanks in advance!

[alfatv]

Re: Interchanging backlights.

You didn't say what are the model numbers.
In any case, the best is to buy new replacement LED strips.
But if you want to experiment, up to you. Power supply controls LED current, so slightly lower voltage should be OK.

[unimatrix93]

Re: Interchanging backlights.

You didn't say what are the model numbers.
In any case, the best is to buy new replacement LED strips.
But if you want to experiment, up to you. Power supply controls LED current, so slightly lower voltage should be OK.

I know it would be the best, but I need to finish up this TV this week sadly.


You say slightly lower voltage is okay. How about slightly higher?

Like 67V on the LG LEDs and 75,6V on the Samsungs LEDs?

[Storyteller12]

Re: Interchanging backlights.

The lights won’t line up with the holes in the reflector sheet

[Rajnhl]

Re: Interchanging backlights.

original are best and available.you can use other brands back light but need to cut new hole in reflector sheet.
each lamp works on 3v.you can use 9 lamp strips.voltage is adjusted depending on feed back ,but margin is small.
or check voltage without strips when switching on tv it will rise up to 80 to 100v without load and then drop.if it goes above 85v you can use 9 led strips.

[unimatrix93]

Re: Interchanging backlights.

original are best and available.you can use other brands back light but need to cut new hole in reflector sheet.
each lamp works on 3v.you can use 9 lamp strips.voltage is adjusted depending on feed back ,but margin is small.
or check voltage without strips when switching on tv it will rise up to 80 to 100v without load and then drop.if it goes above 85v you can use 9 led strips.

Thank you! Will check out the voltage on the PSU and if It's between 85 to 100V I will start cutting the reflector sheet.

[unimatrix93]

Re: Interchanging backlights.

IT WORKED!

I checked the startup voltage of the backlight output on the PSU, it showed 140V. So I installed the Samsung's backlight strips without removing 1 LED from each.



I had to cut new holes on the diffuser paper for each LED, which was tedious but to my surprise it turned out pretty good!




In fact, the display shows almost no white spots because of the stronger LEDs, only in very certain situation...so they are barely noticeable.

Before/After:

[Rajnhl]

Re: Interchanging backlights.

IT WORKED!

I checked the startup voltage of the backlight output on the PSU, it showed 140V. So I installed the Samsung's backlight strips without removing 1 LED from each.

[ATTACH]280477[/ATTACH]

I had to cut new holes on the diffuser paper for each LED, which was tedious but to my surprise it turned out pretty good!

[ATTACH]280479[/ATTACH]
[ATTACH]280478[/ATTACH]

In fact, the display shows almost no white spots because of the stronger LEDs, only in very certain situation...so they are barely noticeable.

Before/After:
[ATTACH]280475[/ATTACH]
[ATTACH]280476[/ATTACH]

white spot only visible when reflectors on strips have different height or shape or oily spots on lamps.