Schematics for Toshiba 40xv645u

[Solderjerk]

I'm playing with a toshiba 40xv645u power supply board that has no standby voltage. The board is a srv2194ww. I've got voltage up to the bulk cap but after that is where I keep getting lost on how it feeds the standby transformer. I was looking for a schematic but no luck finding one. I like figuring stuff out on my own so I'd like to try a schematic first before I actually ask for some help...anyone have a schematic or service manual?

[budm]

Re: Schematics for Toshiba 40xv645u

Can we see good clear high res straight shot pictures of the top and the bottom side of the power supply board? We also pictures of the whole backside of the TV showing all the boards.
Toshiba 75014697 (SRV2194WW, 68-AL43A) Power Supply
http://www.shopjimmy.com/toshiba-750...er-supply.htm#
Is it the exact same board you have?
Check fusible resistor R840 (0.47 Ohms?) to see if it is blown or not.

[R_J]

Re: Schematics for Toshiba 40xv645u

The standby transformer (T841) is driven by ic801, I would check R840, it should read 0.47 ohms, if its open I suspect ic801 will be bad If pins 5 & 7 measure short the ic is bad

[Solderjerk]

Re: Schematics for Toshiba 40xv645u

Yes that is the same board...
Don't have it front of me right now but I will check it and report back...thanks
Still would like to see a schematic tho to follow it, I'm still learning smps

[budm]

Re: Schematics for Toshiba 40xv645u

If you look up the spec sheet of that SMPS IC for the standby power supply; you will probably see the application notes schematic for that IC which more likely to be about the same circuit as used in your board.

[Solderjerk]

Re: Schematics for Toshiba 40xv645u

Poked around alittle on the board...r840 is open, as mentioned, and it then feeds ic801 pin 5. Pin 5 & 7 are not shorted. 5 is not shorted to any other pins, 7 is shorted to 8. Ic801 is a mip2f2 ...pin 5 is a d and 7 & 8 are s so that should be ok. That's all I checked, had to leave for work