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Electronics => Repair => Topic started by: Club_Michas on August 13, 2022, 12:58:08 pm

Title: MDF3N50 replacement for a Sony KDL-75W855C Backlight Driver MOSFET
Post by: Club_Michas on August 13, 2022, 12:58:08 pm

I'm currently trying to repair the Backlight of a Sony KDL-75W855C LCD TV.

1/4 of the LEDs does not Light up and the TVs Power LED is blinking 6 Times Red after the Sony Logo appeared.
I shorted BL_ERR to Ground and the Tv is booting into Android but the Backlight is Turning of after the Sony Logo.

Because I don't have Access to the Schematics I checked some Voltages and It looks like that 1 of the 4 Backlight MOSFETs seams to be faulty but I can't get this MOSFET on Digikey.
I contacted the Support for a suitable replacement but the couldn't help me out.

Does anybody know which MOSFET could be suitable as a Drop in replacement for MDF3N50?

Thanks you everybody on advance for your help.

Title: Re: MDF3N50 replacement for a Sony KDL-75W855C Backlight Driver MOSFET
Post by: m k on August 17, 2022, 07:25:22 pm

3N50 is pretty much 3N50, just find correct casing and you should be fine.

First I found was a bit slower but still clearly in MHz class.
Original Rds(on) is also already quite high so it shouldn't be a big problem.

Title: Re: MDF3N50 replacement for a Sony KDL-75W855C Backlight Driver MOSFET
Post by: fzabkar on August 19, 2022, 05:46:40 am

Just in case you need the datasheet ...

https://www.magnachip.com/wp-content/uploads/2020/10/MDF3N50-2.pdf (https://www.magnachip.com/wp-content/uploads/2020/10/MDF3N50-2.pdf)