This HP1723 17 "LCD monitor came with the complaint without electricity. Upon further investigation, I could hear a soft intermittent sound from two front speakers. Given that the speaker can produce a sound, this means that in case of power properly works and can not start some defective components on the secondary side, the supply voltage to fall, caused to be agreed. The power LED does not light because the signal from the microcontroller (MCU) IC has come.This means that if the MCU has not received the correct voltage from the power supply that will not send output voltage on the power LED.
They can open the LCD cover as usual, be careful not to scratch or leave a mark on the plastic otherwise the client does not accept its broken or scratched LCD monitor. Once removed, the lid is removed, you have another four screws (two per side) for the completion of the inverter / and LessBoard. For some, the LCD monitor, the moment you open the lid, you can easily remove all the cards.
The power and the inverter circuit are retired, while the motherboard and the sound card in a separate border. As already mentioned in my previous article, I do not start right away, troubleshoot and repair a circuit, if I have all the parts with my eyes scanning the first. The supply / inverter power board looks very new and the clearest sign that I could see wastwo filter capacitors (1000UF 16 V) was a slight bulge on top of the jacket. I think that this bulged electrolytic capacitors that caused the power supply is not working properly. I have all the other e-caps, too, but checked all approved.
Normally, when a filter capacitor on the secondary side of SMPS (SMPS) is to have a high ESR value, the voltage drop over half of which many circuits will not work. Since I have already found the bad e-caps, Ibe sure that the secondary diodes (this LCD monitor is equipped with Schottky diodes) are not defective or leaking. In reviewing the Schottky diode (part number and are SRF20100C SP10150) I found both to work properly. Just replace the two bad e-caps with a good LCD monitor has solved the problem.
Now get this, if you choose to repair any electronic equipment in good to analyze where possible, to other streets. That is, if every time you replace just the fuse and the bridgeRectifier, you learn nothing about the problem and will soon become boring. Take my case, for example, after replacing the capacitors are usually several ways to analyze also find out what kind of codes specific components, the type of inverter circuit, which includes direct or Buck Royer?, Because each circuit with backlight four capacitors, ballast, 'How many backlight of the LCD monitor is equipped with what is part of the integrated circuit inverterNumber, which is the voltage inverter chip? How many LED light bars, if the test on the secondary of the high voltage transformer? What would happen if I pull one of the backlight (which will still work, or close?). What is the brightness of the power system when you set the minimum and maximum? You must answer all these questions when you should be good LCD monitor will be repaired. You can apply for these types of questions of other electronic devices. This is a continuous process ofLearn how you are good in electronic repair.
I do not think you replace the caps or safety, without knowing how other circuits or components that are used every day in other circuits. To analyze other way takes a long time, but I can guarantee that your time is worth. She did not go too far in one location, if your thinking, components and simply does not know, have given life around. If you want to improve electronic repair, then you need aTo make you rethink and only you can see the different! Try this approach and believe that the electronic troubleshooting and repair of the LCD monitor will never be the same. Have a great and a fantastic year!