MPC 2000 screen backlight replacement/mod

Good day to all !

I am opening this thread since I read some ideas floating around about changing the backlight of the screen, but I couldn't find any pics or info about it, maybe it will help somebody.

I have bought an working MPC 2000, but it had the classic issue with the burnt and faded screen and 240 $ to me seemed a little bit to much for a new LCD screen.



First thing I have done is to clean and replace the burnt polarizing film, but since I have used one for smatphones screen repairing it was still a little bit too dark.



The backlight CCL was still working but it was not powerful enough so I figured I could replace it with some LED COD band 3 mm wide so that it can fit inside the screen,





The band is supplied with 12 v DC - I have used the input for the CCL converter board.

This is the result

Where did you find the led to order?

Never knew about these COB bands... or passed them by in DIY supplies
Price looks great and they are splittable (roughly) in inch units.
thanks for the hint

richie wrote:Where did you find the led to order?

Don't know about OP, but mouser.com is usually the place i go for everything electronic

richie wrote:Where did you find the led to order?

I have bought it from some local store, similar to Amazon, I am living in Romania, Europe. I think even the RGB normal LED strip could work, could be even cooler to have the possibility to change the backlight color of the screen

cristianneagu wrote:

richie wrote:Where did you find the led to order?

I have bought it from some local store, similar to Amazon, I am living in Romania, Europe. I think even the RGB normal LED strip could work, could be even cooler to have the possibility to change the backlight color of the screen

Thanks for responding.

The reason why I ask, putting a standard small led strip like the ones we can easily find will generate a lot more heat at that voltage, and consequently cause the strip between the pcb and the lcd to separate, creating way more lines or ruining the display all together.

chilom wrote:

richie wrote:Where did you find the led to order?

Don't know about OP, but mouser.com is usually the place i go for everything electronic

Yes I've worked with mouser a decent amount. I still have no idea what he means by "COB Bands" but for the most part, I have not seen a direct CCFL to LED in the CCFL form factor anywhere. I've only seen alternatives like an LED EL strip which has an LED on the side of it and subsequently illuminates the strip.

The only mod I've seen to replace the CCFL to LED was one that uh, I think a dude from France that has a site or a facebook called Haarp laser made a few kits for the MPC 4000, but those 4000 screens are engineered way better than the fragile 2000/XL screen.

A COB (circuit on board) band has the LEDs and full control circuit „printed“ on a strip.
Sold in units of meters and can be split every inch.
You just solder a power connector to whatever segment cut off and that‘s it, as pictured above.

Iirc the french dude soldered SMD LEDs in a row and placed a circuit to drive the LEDs in the inverter housing.
Similar to my own crude approach of twisting decoration LEDs in a row, steel 5V from the inverter and place the circuit with the switch behind the MPC.

A COB band has full regulation at each possible split point, You could make roughly 40 individual lights from 1m of band... or 15 segments of 3“ length each. Cool stuff.

Telefunky wrote:
Iirc the french dude soldered SMD LEDs in a row and placed a circuit to drive the LEDs in the inverter housing.
Similar to my own crude approach of twisting decoration LEDs in a row, steel 5V from the inverter and place the circuit with the switch behind the MPC.

A COB band has full regulation at each possible split point,

Thanks for confirming man, I appreciate it.

From what I believe I remember, the design on the 4000 screen housing was a bit different where the led strip he designed can fit in there without a worry of overheating and separating the board from the controller.

you can see the details of his work here :
or when zoomed :

Src: https://www.harpelaser.com/files/mpc_fo ... _guide.pdf

Yup that's it there. The thing with that is it fits into a separate bracket, so the amount of heat it would expel would not be of any danger to the screen.

Come to think of it, I wonder if layering some kapton tape on the 2000 screen where the ribbon folds could help protect it some against the heat, which could cause the ribbon to otherwise crack.

There‘s almost no heat emission from LEDs if chosen properly.
Regarding COB bands: the LED driving circuit (as pictured above) is printed 20 times per meter on the strip, of course not exactly the same but a functionally identical circuit. Impressive.
If this would emit significant amounts of heat, there would be problems with mounting.
Imho it‘s safe to assume these things get hand-warm in worst case.
(I haven‘t tried one yet, but will do soon)

Telefunky wrote:There‘s almost no heat emission from LEDs if chosen properly.

keywords here are "chosen properly". Powerfull LEDs can of course produce heat, a lot. the best is to look at the datasheet. typically theses one (for example) : https://lumileds.com/products/cob-leds/ ... h-density/ when looking in the details for the maximum junction temperature. they heat up to 150 degrees (celsius)

Yes... I only recently learned that there are high voltage LEDs (from a LED array in a cheapo desk lamp), driven by a regular wall outlet.
A cap on the circuit had 400V printed on it.

But such bands as suggested above (3mm size) with a 9V power connector are way different from the units you linked above, targeted at spot and tracking light apps.
Size start at 6mm per LED with 350 mA current for a single LED, which is huge.
Btw their specs are based on 85 Celsius junction temperature, the 150 Celsius is absolute maximum.