Nuova Marea MV-1501 (Unicont) Blink and off at power on

[sententia]

Re: Nuova Marea MV-1501 (Unicont) Blink and off at power on

I also think that the inverter is ok. It does look so .... The brightness adjust did not work though.

The logic board outputs 3.3V to button board and lcd (it has a jumper to select 3.3V and 5V) .

The logic board has a lot of small caps i have not tested.

By the way the display has very few working hours.

[sententia]

Re: Nuova Marea MV-1501 (Unicont) Blink and off at power on

Struggling with the datsheet any chance of cleaning up the top of U1 and getting a close up picture to show the part number. I have spent many hours looking for parts using wrong numbers B-3-8 D-O 0 2-S-5 and so on.

Selldoor,

I am also trying the same thing. With all that soft silicone like material on everything it is impossible to distinguish components.... i will try again if i manage to find something.

[budm]

Re: Nuova Marea MV-1501 (Unicont) Blink and off at power on

I would concentrating on getting the logic board to work first since we know that we can get the backlights to come on. Logic board does not care if the backlights are working or not, it should produce pictures on the LCD panel, backlights are just the light source and can be any light source to light up the screen.

[selldoor]

Re: Nuova Marea MV-1501 (Unicont) Blink and off at power on

This might be interesting I have not tried the links yet but it about a big brother monitor MV-1701
http://morautomatica.spb.ru/eng/index.php?id=71

I was moving on to the logic board and found that.

What is the part number on the black component top right with 3 legs or 2 and a half legs

[selldoor]

Re: Nuova Marea MV-1501 (Unicont) Blink and off at power on

Link to the 1501 in case you missed it

http://morautomatica.spb.ru/eng/index.php?id=56

[sententia]

Re: Nuova Marea MV-1501 (Unicont) Blink and off at power on

Yes that is the one. Manufacturer site is http://www.unicont.spb.ru/

The ic on the logic board must be a voltage regulator. I cannot make what is written on it, but on board there is I,O,G on legs and the output is 3.3V

[budm]

Re: Nuova Marea MV-1501 (Unicont) Blink and off at power on

"I cannot make what is written on it, but on board there is I,O,G on legs and the output is 3.3V" That looks like to be 3.3VDC Voltage regulator IC, the voltage at the 'I' (input) is 5VDC?

[sententia]

Re: Nuova Marea MV-1501 (Unicont) Blink and off at power on

Yep that wasn't very clear. The pcb has the labels...

Yes input voltage is 5V.

[budm]

Re: Nuova Marea MV-1501 (Unicont) Blink and off at power on

So the logic board is getting the correct 5VDC feeding it OK, which means those 3 filter caps you replaced in that 5V Buck regulator are OK, and then the 5V is stepped down to 3.3V with LDO regulator. I do not know far we can troubleshoot this logic board without the diagram. The unit just went out by itself?

[sententia]

Re: Nuova Marea MV-1501 (Unicont) Blink and off at power on

Yes the unit went out by itself. I was working, and we try to operate again after some time and it was like this.

I spent some time checking almost all electrolytics on logic board but didn't find anything wrong.

It is not possible to find any schematics i think, although there are some schematics around from other manufacturers that use the same chip.

I contacted the company yesterday and got a response today. I want to check if i can get replacement boards from them.

[selldoor]

Re: Nuova Marea MV-1501 (Unicont) Blink and off at power on

Can you have a close look at the joints on that lelon cap that is on its side.
They look ringed - when it is on what voltage does it show.

[sententia]

Re: Nuova Marea MV-1501 (Unicont) Blink and off at power on

I did put the lelon that way to have some access on the top layer as one pin on bottom side didn't have any tracks (i lifted the small bit on the bottom around the joint...).

The voltage on that capacitor is 12V.

I include another pic without the glue.

[selldoor]

Re: Nuova Marea MV-1501 (Unicont) Blink and off at power on

Hmm - going back to the on/off pin on the inverter board - when you say you hard wired it -I see this end of the jumper wire but what did you connect the other end to?
Did you cut the white wire as budm said and connect to that?

[sententia]

Re: Nuova Marea MV-1501 (Unicont) Blink and off at power on

The other end of the cable was connected to pin on/off of the connector. I though the track was cut somewhere and connected it to wrong position on the board (lucky nothing seems fried). I didn't remove the on/off connector coming from the logic board.

Do you think i should try to start it properly but putting 3V on on/off pin of the inverter board?

P.S. I got an answer from manufacturer. Great support and fast responses! However the monitor is discontinued and they don't have any replacement parts for this one..

[sententia]

Re: Nuova Marea MV-1501 (Unicont) Blink and off at power on

Connecting 3.3V to on/off pin of the board does indeed light up the backlight. I disconnected the on/off cable coming from logic board.

No difference on anything else though....

[selldoor]

Re: Nuova Marea MV-1501 (Unicont) Blink and off at power on

Not sure I understand that can you say it another way? did you use a battery or something to apply 3v to the on off pin on the inverter board?
Can you do a picture of the bottom of the Main Board - dont think Ive seen one?
Next might be to trace from where the white wire connects to the main board to see what that goes through - may be one of those little switching transistors stuck.

Good/bad news from the manufacturer - did you ask if they had any diagrams
for any of the boards? - always worth a try also if they are only answering what you
ask and not thinking outside the box did they use the same board in the 17 inch.
and is that available?

[sententia]

Re: Nuova Marea MV-1501 (Unicont) Blink and off at power on

Yes i did supply 3.3v through a 10K resistor from external source.

I have traced a bit the on/off wire on the logic board and it does connect to some of those sot23 transistors. I will look deeper into it.

I have noticed that one end of power led goes to inverter and connects to IC as noted in picture and other end goes to logic board.

I asked the manufacturer if they can provide any schematics at all. Wait and see.

They do offer now 15" but only the box is the same. Panel, logic, inverter & supply are different.

[selldoor]

Re: Nuova Marea MV-1501 (Unicont) Blink and off at power on

mindreader? I was also looking at the button board/is the led on there - I suppose first thing might be to actually test the led?

As an aside I have interesting but maybe not useful links
Search for LTM170EU-L31 seems to use that board??
EDIT maybe not that is just a panel perhaps one that can be driven by this controller - It came up in google images.


and so to here
http://www.etradeasia.com/products_d...ptop_LCD_.html

Looks familiar but there is no big chip? and other things differ - perhaps
it is a bare board and they program chips depending on which screen you have?

[sententia]

Re: Nuova Marea MV-1501 (Unicont) Blink and off at power on

looking at panel controllers i realized that there are a lot of compatible boards at least for the lcd panel. Even at ebay there are compatible board for 8$ and board+inverter at 30$ !

I start to really consider the option of fitting a different logic controller as compatible ones have same lcd connector etc.

Now about the current board. The so8 ic that is under the bent Lelon cap is a mp9141es which is a step down converter. I think power wire connects to one of the pins and to a small sot23 transistor.

I found an equivalent datasheet. Pin5 is indeed 1.22V and enable pin is at 3.7V which is much higher than the enable (1.7V) needs. What i saw though is that filter capacitors should be low esr caps! I doubt that the Chengx were low esr so i replaced with standard caps. I don't know if i should try to replace those 3 caps with low esr ones...

[sententia]

Re: Nuova Marea MV-1501 (Unicont) Blink and off at power on

Tested with low esr caps. No difference.