Dell LCD conversion to LED light

Thread Starter

Poppa D

Joined Aug 30, 2020
17
Dell 24" Monitor
MV230HM-N30 B4
S2318HN/S2318NX

Cat knocked over and broke LCD screen, am trying to convert to LED light utilizing existing LED edge back light strip (4 groups of 16 LED lights=64 total) These are numbers on LED strip, E466169XY-MC 94V-0 and 1602 N52PBY5 C52NA23. Only one PCB that's got power section and video section see attached pdf's.

After tear down reattached connectors and turned on: Power light came on, LCD flickered several times, first 16 LEDs came on for 3 to 5 seconds and then both shut down, power light remained on. After that nothing came on except power light (LED)

The following DC voltages were taken with everything connected to PCB and powered with 12V adapter that came with monitor

Code:
PIN         LCD         ON/OFF         LED
1           5           3,3             0
2           5           3.3             0
3           5           3.3            12   pins 3&4 go to
4           0           2.7            12   20 and drop to 12
5           0           grd             0
6           0           3.3             0
7          grd
8           0
9           3
10         1.5
11           1
12         0.2
13         2.5
14         grd
15           1
16           3
17         grd
18          0,1
19           3
20           0
21           3
22          1.5
23           1
24         grd
25           0
26          2.5
27         0,1
28          3
29         0.1
30          3
Checked individual LED's with 3volt power source and all seemed to burn (really bright), so think they are okay. Don't know how to start trying to jumper contacts out to get LED's to come on. There are no descriptions/legends on any of the components and have been unable to locate any diagrams for monitor or PCB. Know I can just junk it all and go buy string of LEDS and install, but would rather burn this one up trying to get it to work before buying something else. Any suggestions on how to proceed would be appreciated
 

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Thread Starter

Poppa D

Joined Aug 30, 2020
17
Thanks Bertus it helped a lot! Here's photo of LCD connection with voltages typed in best I could. The green bars are ground and appears that contacts 8 thru 30 connect to U1 thru U5, leaving contacts 1 thru 6 as possible control circuits (7 is ground). Just to the left of ribbon connection are 2 test ports (small gold circles) labeled "SCL_EEPROM and SDA_EEPROM" if that is significant .
DELL LCD.jpg
The 2 extreme contacts (0,31) do not connect to the ribbon and are grounded. It appears the 1, 2, & 3 all connect to the blue P component any idea what this would be? Just above "0" resistors are 2 test ports labeled "SCL_PG and SDA_PG" ? Could the LEDs need an OK from the LCD before working? If so what's your best guess on how to supply that signal? Thanks Poppa D
 

Thread Starter

Poppa D

Joined Aug 30, 2020
17
Been a while but finally had time to look at this some more and traced out continuity on controller at LED/POWER side of PCB
DELL Power Circuits.jpg
How to?
1) To get high voltage to LEDs the N channel transistor gate has to be energized (max 20V) can this be done from this controller
2) Seems source on N channel transistor is going directly to ground is this correct
3) Pins 1, 14, & 16 all go to R826 & R827 and then to LED pins 1 & 2 very confusing how all this works
4) Any other information I can provide, still trying to understand
 
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