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rodarapan

MA6930 Power Supply IC

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Hello All,
Greetings... I have been searching for any datasheet info on this power supply IC (MA6930), and so far after almost six months, I haven't found any. The monitor was manufactured by Mitsubishi but it is sold by Digital Equipment Corp. (DEC).
Any help will be much appreciated.

Thanks and regards,
Rod

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Hello,
Thank you for your reply, appreciate it. Sorry that I did not include any information about the monitor. Here are a few details about it that I have found on the label:

Digital Equipment Corporation
Model No. VRCX1-W3
Chassis Family: W9105
FCC ID: BGBTFW9105K
Power Supply Board Part No. CT920B3260
Another number on the label which might be relevant:
CP775C229A20

Also, I would like to find a datasheet of MA2810 which has also failed on this monitor's power supply. The manufacturer's logo on both power supply IC's are Shindengen, but when I went to their website, they don't provide any schematic or pin assigment for the said IC's.
I hope somebody in this forum can help me with this...

Thanks and regards,
Rod

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Here is what i found so far.

power supply IC MA6930

MA6930 CP 267P09202 IC MITSUBISHI MONITOR 57 01

MA6930 Power Switching Regulators

http://www.pimpworks.org/dec/manuals/

http://www.pimpworks.org/dec/

http://www.chipweb.de/dsl/index.php?menu=6&level=2&id1=94

http://www.ibh-dd.de/alpha/as500.pdf#search='VRCX1W3'

http://h18000.www1.hp.com/products/quickspecs/SOC/QB004KMW.DOC

http://h18000.www1.hp.com/products/quickspecs/SOC/QB0051MW.DOC

http://www.ibh-dd.de/alpha/as500.pdf#search='VRCX1W3'

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Hi,
Thank you all for the replies... Looks like I am nearing to my quest of finding the correct schematic or information regarding this monitor and the blown parts. When I look at the monitors which was presented to me on my search, I found it that it look similar to Mitsubishi Diamond Pro 91TXM or sometimes refer to as model TFW9105SK. If anybody can point me to the right direction for the schematic, I would be very grateful.

Thanks and regards,
Rod

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Hello All,
After two days of intense searching, I haven't come across any datasheet for MA6930, or schematic of the monitor Diamond Pro 91TXM with model no. TFW9105SKTKW by Mitsubishi. The datasheet for MA2810 that was posted here did not help me much due to no pin assignment information which will give me more idea on how the circuit works. I was wondering why Shindengen does not provide the diagram or at least the pin assignment of the MA2810 pdf they have on their website.
The schematic will help me very well if I can get hold of one... Any help will be much appreciated...

TIA...

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Hello...
Unfortunately, PT6930 is totally different. The MA6930 IC is directly driving the main transformer that controls the ground connection. The other IC MA2810 controls a smaller transformer to the ground as well. And both of them got shorted out. That's the main reason I want to get hold of the schematic or at least pins assignment of the IC's so I can make changes to the circuit if necessary. We have three of them failed at the same time with the same IC's shorted out. So, I presumed there must be something wrong with the design of the circuit surrounding the IC's, like not enough protection, etc.
Also, buying those parts seems tricky as well...

Thanks and regards,
Rod

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Hi, rodarapan
can you please read the label on lopt transformer?

The label on mine is partially unreadable... is like 334P....

I think i can help you with your power supply problem!
My power supply is working!

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Fela,
Hi, I just finish dismantling the input board of the two Mitsubshi's, I have here in the workshop, and both of them does not have a readable part number which was printed on a small paper. The printing has faded and unrecognizable. I even detached one of the sticker and placed it under a microscope to see if I can read it, but that too failed to decern any ligible print. Sorry about that...

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Hello again,
No, I don't have any diagram for this. I am still on the look out for the schematic diagram of this, and also the datasheet with pin assignment of the two IC's MA2810 and MA6930 which will help me modify the circuit to get a better understanding why they are failing. So far, one of them have failed MA2810, MA6930, and two open resistors R918, R922 which are 10 ohms 5 watts. The other one, were all of the above parts plus burnt R905 (130 Ohms) and R906 (56 Ohms).
Even the IC's were very hard to locate especially the MA6930...

Thanks and regards,
Rod

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Just thinking!!! Is it possible that a replacement IC for this discontinued MA6930 be available? Maybe someone have a cross reference book that will give a substitute for this like in a transistor? What I know about it, this IC have a built in MOSFET to drive the main transformer on this monitor's power supply.
Will appreciate any thought on this idea. TIA... :)

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Thanks for the User Guide, HotWaterWizard... Appreciate it!!!
I am still trying to locate a schematic for 91TXM Diamond Pro, and the part MA6930. The MA2810 is readily available but I cannot use one without the other. Still cannot find a replacement or substitute for MA6930 which I think is discontinued by Shindengen already.
I have written to Nec-Mitsubishi.com support and they asked me to ship the item to their repair center for repair but this monitor weigh-in at 78 lbs/35 kilos, which is not too light to ship. Spending money on something I can repair myself is not my idea of fun...

The Quest Continues...

Thanks and regards,
Rod

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Hello Again,
    Just to give a heads up... Another two of the same monitor failed and still haven't found any schematic for the monitor. I have inquired on some of the online stores I have found but still no luck in finding the parts.

Thanks for any help...

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