Re: Samsung BN44-00807E Low Backlight

SOLVED - well the culprit are bad AOD9n40 devices as replacement - yuup ebay. As you suggested probably counterfeit devices from china.

Fortunately I has an original MOD9n40 that I has carefully pulled from another board and installed it into the BN44-00807E that had smoked multiple AOD9n40 devices.

MOD9n40 running cool event with mainboard pulled and pushing full brightness on the LED backlight.

Going to run the new backlights at 12-13 - no higher.

Have on vertical black line on the screen...

Re: Samsung BN44-00807E Low Backlight

Image of board area and the AOD9n40 in package. [ATTACH]277512[/ATTACH]

[ATTACH]277513[/ATTACH]Re: Samsung BN44-00807E Low Backlight

Image of board area and the AOD9n40 in package. [ATTACH]277512[/ATTACH]

[ATTACH]277513[/ATTACH]...

Re: Samsung BN44-00807E Low Backlight

Update:
Found that is brightness was turned up past 80, the backlight increased to proper levels.

BUT THEN...
Q9102C began smoking and burned.

Replaced q9102C again, retested and lights come on but chip is getting way too hot.

Checked backlight strips with the 'backlight tester from jimmy and they are working fine ( all strings light) . No shorts measured to ground.

I want to measure the current to the lights but need to acquire a clamp on DC tester. an AOD9N40 is good for 9amps...

Symptom is dim backlight - this set came in with almost no backlight.

Samsung UN55JU6500FX2A

1 - Replaced all backlight LED strips (set had lots of hours at level 20 backlight)
2 - Changed out what appeared to be a bad Q9102C on BN44-00807E - not shorted or burned but appeared to be open. I was able to read (with difficulty) the part number - however I may have misread it - Can someone confirm that this is indeed an AOD9N40.

Backlight improved significantly - about like it would be set to a level 3 or 4. Setting all the way to 20 seems to...

Re: New Members - please post your introductions here

Hello, Warren smith, Charleston SC. Former product manager for Infor Erp software. Now retired and hobby is electronic repair. Ga tech grad, class of 1984, just after vacuum tubes.

Thanks for helping me out with questions I may have