Among the common problems in Samsung 153v LCD Monitor was display dim. When you get nearer to the screen and start to see the display under dark atmosphere you really often see the display however it was very dim. Should you press the leading panel button, the on the watch's screen display (OSD) would made an appearance which proof the primary board, driver board and LCD panel is working and the issue is within the inverter board. The purpose of inverter board would be to generate an ac wave from electricity current to energy in the lamps that was situated at the very top and bottom from the LCD Monitor. When the inverter board has problems it wouldn't illuminate the lamps and what you might see merely a dim display.
I still could recall initially when i first experienced such problems very long time ago and due to not enough information, I possibly could not solve it. Used to do contact my repair buddies to requested concerning the solution but nobody capable of giving me a solution. Even when you surf the web for "Samsung 153V LCD Monitor dim display repair", you wouldn't think it is. Because of this I must do my very own research to obtain the answer and I have never quit. Winston Churchill once stated "Never, never, never quitInch. I am delivering the answer simply to my loyal people or customers only-interesting support.
Let us begin right now! When the cover and also the internal aluminum casing were opened up I saw two bulged filter capacitors in the secondary side of switch mode energy supply. The worth was 470 and 1000 microfarad 25 volts. I saw four more electrolytic capacitors situated in the inverter board have transformed color and also the value was 47 micro farad 25 volts. Going through the entire board with my ESR meter I discovered another capacitor faulty (220 uf 25 volts) that was close to the fuse (3amp). Because this capacitor was situated in the same line using the fuse, I presumed the fuse can provide way too. True enough, checking the fuse by having an ohmmeter says it's open circuit.
Now, the actual problem faced by many people electronic repairers who handles this model was, after changing all the components over the LCD Monitor still wouldn't work-will still be dim! First you need to request yourself why the fuse blown? Can it be triggered through the defective capacitors or something like that shorted past the fuse line? The closest circuit towards the fuse was the beginning circuit that comprised of a set of NPN and PNP digital transistor (4k7 +4k7 resistor included in the transistor). Another LCD monitor designed used the mixture of C945 and A733 in start circuit. Incidentally the part number for Samsung 153V start circuit transistors were the A6J (PNP digital transistor) and also the A8J (NPN digital transistor) as proven within the picture.
Sometimes only these transistors have issues (shorted) that triggered the fuse to blow however in the above mentioned situation both digital transistors are examined okay. Since both transistors were working, the concentration need to be within the four ic's that drive our prime current transformers since the 12 volts current was delivering to all these ic's. These 4 ic's have numerous part amounts and the most typical one which the maker used was 4532m. Some board used the AD4E10 and BBD3N13 part number. Right now it is extremely challenging the datasheet or technical specs with this number even on the internet search.
Are you aware what's inside these IC's? It's really a set of P-funnel along with a N-funnel mosfet included in it. And are you aware that it may be test having a meter? Yes, if you are using the height atlas component analyzer, it might prompt for you the end result. In the result what you'll get are N funnel FET situated at pin 1 (source), pin 2 (gate), pin 7 &lifier 8 (drain and both hooks joint together internally). For P funnel FET, pin 3 (source), pin 4 (gate) and pin 5 &lifier 6 (drain and both hooks joint internally). In the above test I discovered a couple of these ic's have shorted. Changing both of these shorted IC using the capacitors and fuse place the LCD Monitor to existence!
Yet another factor I must share about this model could be that the inverter PWM IC BIT1305 was quite robust and barely gave problem.
Jestine Yong is really a electronic repairer along with a author, for additional electronic and LCD MONITOR repair information, check out his website at http://world wide web.electronicrepairguide.com/lcd-monitor-repair.html
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