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Help !!! Need shematic for Eizo L360 TFT

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OBDTech

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Hi !

My "good" old Eizo Flexscan L360 has stopped working. I now urgently need a service manual or shematic for it. I already tried a lot to find one in the web...but after days now...I give up. :cry:
Maybe someone can help me ? I really would appreciate to get some help.
The TFT is getting totally bright when it gets a signal from the GC.
OSD looks normal. Brightn.+contrast is already pulled down to 0%. Auto justage works but change it also to 2% contrast and 0% brightness.
There´s a M52744SP, maybe it wrongly reads the signal ?

Any help is welcome.

Thanks in advance !!!

Vince
 

Hi,
if you feed the monitor with analog signal, most probably the first ic (amplifier and other analogic video functions) is lost. the problem doesn't seem to be in digital part, otherwise the osd wouldn't work. voltage spikes, voltage breakdowns or poor (or none) grounding of both the monitor and pc can cause the failure of that analog chip. also, do not miss to check your video card. it may be gone as well.
 

Hi Pisoiu !

Thanks a lot for your reply ! There´s (right after the monitor cable plug) an input selector called BA7658AFS. The monitor has 2 inputs which basicly doesn´t matter at all I guess, both inputs same error.
I think you are right, the OSD looks good and blank signal works (when the GC changes to it).
The problem is to get these to chips, here in Germany. I guess the switch is easier to get.
Btw., the A/D converter are getting really hot, do you think that´s normal especially when contrast and brightness is pulled totally down ?
Is it possible to simply bridge (taking out the fuses for RGB) the lines from swtich to amplifier ? I am sorry to ask that much, but I am a just starting with monitors since 2 months.
Another thing...the input voltage to switch is 3,62V but the output only 2,1 something. Is that normal ?

My GC (Laptop) works fine and I also tried it with my PC. Next week I get an ESR(Elko)-Tester maybe it´s one or more defective capcitors.

I downloaded datasheets for the BA and M52 but the problem is, I really don´t know how to measure it excepting the Vcc. I got a Hameg 203 20MHz Oszi, maybe that would help (if Iwould know how,LOL) ?

Again, many thanks for your help !

Ciao, Vince.
 

Hi,
A/D converter, especially the high speed ones are energy eaters. Do not worry, it is normally to get hot. As long as you can see the image on the screen, you may assume that you have a working adc. The contrast and brightness do not affect the power consumption of an adc. Its power consumption is mainly dictated by its sampling frequency, not by characteristics of the input signal. Voltages seem to be ok. Regarding the passive components: in extremely few cases these componens fail and generate such defects like in your case. My guess is that you have to search for defective active components. The input switch you told me about can be the cause, but not necesarily. If the image have the same aspect regardless of the input you use, the chances are low. Anyway, you can try to bypass it in the following way:
-use the oscilloscope to identify the inputs and outputs. put a totaly red image on screen, then see with the osc where it gets in into the chip and where it gets out. do the same with green, blue and syncH, syncV (note that maybe synch and syncv do not enter into this chip, they may go into a digital processing chip). extract the switch chip gently, do not destroy the pcb under, maybe you will have to put it back. then make the bypass between red in and red out..and same with others. before starting with this, make sure that ic is only an analog switch. if the chip performs other functions over analod signal, this procedure will not work.
also, as a general rule, make a visual inspection of the entire board and look at the following components:
-power disipating devices (transistors from power supplies, coils, etc.)
-mechanical components (signal inputs, power inputs, adjustments)
sometimes these components can produce bad contacts between them and the main pcb, due to aging, vibrations, etc... if you see a poor soldering joint, remake it.
good luck
 

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