Astar MP-27BH power transformer.. will pay

Nov 09, 2009

- or send a link where i can see the board, or the image or post it.

Nov 09, 2009

- include these in your search the osc IC near to it

maybe like these





you may need to use a magnifying glass to read the label

Nov 11, 2009

- "PC817 Sharp" is an optocoupler it rarely goes bad, except when the main regulator output transistor is always get busted.

post the other part number that you can see ( regulator )

Hint: the regulator ( output IC) is directly connected to the transformer you are looking.

follow the blue arrow

Nov 11, 2009

- the two are the Regulator Output Transistors it is controlled by PC817 and there is an oscillator IC driving the said transistors Actually they are Power FET's

Nov 11, 2009

- like wise with these blue arrows

Nov 11, 2009

- here is the main osc IC

Nov 11, 2009

- verify if the chopper transformer windings is still OK , you might have an almost zero resistance if it is still good.

there should be good resistance on the primary and the secondary.


the primary is the one near to the main cord and the secondary is going to the diodes with the capacitors.

if the windings still good and no burns or burnt coil , you can put it back later and dip it to an electrical

varnish after having to put it back, before bringing it back to the board.


you should also have voltages on the primary of the chopper would be equal to the voltages on

the 180 uf 450V capacitor.

if you have step down transformer might be better to use it first when doing these steps.

Nov 11, 2009

- since the transformer is already extracted , and we're still looking for one

i have found one that might be similar to your power board


http://www.shopjimmy.com/fsp-fsp205-5e01-power-supply.htm

http://www.power-on.com/lcd205-5e.html

Nov 11, 2009

- since the insulation (plastic) as you have mentioned have melted there could be other components

that might be needed to replace.

unless the output voltages are correct with the original board , there is a possibility it might work.

it could also be on the other boards.( inverter circuits)

that is why i am asking for the original output voltages of the power board.

since you have mentioned there is sound then most probably some part of that power supply

is good, taking off that transformer will produce no output at all.

i just hope your assumption that replacing the transformer will resolve the board problem.

it could also be from the load side of the chopper transformer, starting from the diodes to the

regulator. PC817 will just turned off the osc if fault is detected on the secondary side.

Nov 11, 2009

- typical output voltages are

DC Outputs (Amps Max/Min): +24V (6.0/0.0A), +12V (3.0/0.0A), +5V (4.0/0.0A), +5VSB (1.0/.050A)


your problem might be on the +24 V line , include the other components with it.

Nov 11, 2009

- and these are the output voltages of the FSP205-5E01

Nov 11, 2009

- the SMPS transformer might be similar to yours