Sharp LC-32SB21U No Power. Schematic needed for RUNTKA448WJQZ PSD-0568

[A Man]

Hello,
I have a PSU/inverter board that has a blown main fuse as well as several shorted zener diodes. I'm looking for the schematic and component list so that I know what the diode values are. Or if anyone has any knowledge as to how to determine this in the absence of said schematic, that would be great!

Thanks!
Adrian

[A Man]

Re: Sharp LC-32SB21U No Power. Schematic needed for RUNTKA448WJQZ PSD-0568

Anyone??? I'm attaching pics of the power supply side of the board top & bottom. The MOSFETs that I removed from Q7112 & Q7117 are R5007ANX. I accidentally shorted the Drain & Gate and/or to ground on the heatsink that covered them when I was checking them. *goob noob* The zener(?)diodes that I blew & removed from D7115&D7116, D7117&D7119 had 24N written on them.

This is only my third attempt at SMPS repair. Repaired one with bad caps, second had bad IC that is on backorder and now this. Any help would be great!

Thanks!
Adrian

[mdwridge]

Re: Sharp LC-32SB21U No Power. Schematic needed for RUNTKA448WJQZ PSD-0568

I am looking for that schematic too, I havent been able to find it either, but you really helped me out with the part numbers you have on here, someone removed them from the board im trying to fix and now I dont know what the original part # was. If you have any other pointers from the repairs you made, any help would be appreciated, Thanks!!

[budm]

Re: Sharp LC-32SB21U No Power. Schematic needed for RUNTKA448WJQZ PSD-0568

One of these service manuals may match your Sharp chassis:
http://elektrotanya.com/?q=showresul...oria=&kat2=all
Not sure if it will have the SCH of the backlights inverter section.

http://www.shopjimmy.com/sharp-runtk...t-inverter.htm

[randtek]

Re: Sharp LC-32SB21U No Power. Schematic needed for RUNTKA448WJQZ PSD-0568

The facility I work for will not allow me to upload manuals. However, I have just looked through the entire service manual for that model series, and it does not give ANY information about the power/inverter board - no schematic, board diagram, block diagram, parts list, or anything else pertaining to the power board. Unfortunately, this is the way most of the manufacturers are going. They do not intend/want these units to be repaired to component level, so they don't release complete schematics anymore.

[mdwridge]

Re: Sharp LC-32SB21U No Power. Schematic needed for RUNTKA448WJQZ PSD-0568

Thanks for the replies. I was able to find that schematic online that you are talking about, however as you say, there was nothing about the inverter section, Just for the main board. I have enough information to order a replacement mosfet, however the Zener Diodes that are missing really trouble me.I took out a similar diode on the board to use for testingand have tried to find the breakdown voltage , going up to 55vdc already and still no luck, Im surprised the voltage is that high there, unless it is being used as a regular diode. If anyone has any knowledge to share about finding its value, that would be great.