AG Neovo X-17A

[sabre504]

HI all
have an AG Neovo X-17A with power problem .

12v 3.5a external psu working no power to screen
Have found the problem on the main board Q801 chip burned out and the only readable numbers on are RSS050 on top line and on second line just the last digit is 3

Have found a pdf relating as close as i can but not sure if its correct just wondered if anyone had done these before or had a board showing correct numbers that they could quote to me .

Think the chip blew from a surge as i cannot find a fuse on the board
sheet and pic attached
Thanks in advance
Paul

[retiredcaps]

Re: AG Neovo X-17A

1) What is part number U801?

2) Check the two diodes just to the right of Q801 to see if they are good.

[sabre504]

Re: AG Neovo X-17A

Hi Retired caps
as i said i can only read top line RSS050 bottom line burned away apart from last digit which is a 3 .
Diodes i am going to have to take off board to test as i cant get any reading
will message back when i have done this
cheers

[retiredcaps]

Re: AG Neovo X-17A

Diodes i am going to have to take off board to test as i cant get any reading
will message back when i have done this
cheers

U801, not Q801. U801 is just above the power adapter plug.

Diodes can be tested in circuit first and then removed if the readings are suspicious to confirm. Use the diode test function on your multimeter.

[sabre504]

Re: AG Neovo X-17A

Hi sorry mate misread my fault
U801 - top line AIC 1578ps
bottom line 673ca

Am taking diodes off board as reading out of range then in then out again so taking them off so as no interference from other parts just to be sure

[sabre504]

Re: AG Neovo X-17A

Diodes reading open in both directions
PJ65 SS14

[selldoor]

Re: AG Neovo X-17A

I think this U801 - top line AIC 1578ps
must be one of these

[retiredcaps]

Re: AG Neovo X-17A

Thanks selldoor for the datasheet.

@sabre504, refer to datasheet. See if AIC1578 the VCC pin is shorted to GND pin.

[retiredcaps]

Re: AG Neovo X-17A

Diodes reading open in both directions
PJ65 SS14

This has SS14 on the part number.

http://parts.digikey.com/1/parts/419...-sma-ss14.html

I'm not sure if this is the right size though.

[sabre504]

Re: AG Neovo X-17A

Hi
VCC to GND not open so test ok
Diodes are correct but cost to much post here from digi key unless you put in large order .
Will source those elsewhere (probably got some not looked yet)

Still trying to find out what Q801 is tho

[sabre504]

Re: AG Neovo X-17A

Also found this on another site

Hi friends ..
I have 2 of these in for repair with exactly the same fault on each ..

Loading the 12v psu brick when connected ..

Inductor L802 gets mighty hot
FET 8 pin smd Q801(RSS050) gets too hot to touch as does Zener diode ZD801 (suspect its possibly 6.2v),,
The fet is dead I suspect ...as is the zener ...definately short circuit..
These components have been replaced with what I think are close matches ...
but the zener and the fet failed again ..immediately ..
So I suspect there is more to it ..
Problem is I have no sevice info ..as usual ..
I've even contacted what I believe to be the Neovo agent ..and they say there is'nt and never has been a schematic available ..
These guys _do_service these montors ..but only at board swap level ...which is a joke..
Anyone come accross these monitors ..
Any service info or hints would be most appreciated ..as the cost of pcb replacement makes the repairs non viable..


Not exactly confidence inspiring

[selldoor]

Re: AG Neovo X-17A

"Still trying to find out what Q801 is tho"


Hi - Thought you had bottomed this early on when you posted the data sheet.

Perhaps one of these would fit http://uk.rs-online.com/web/p/mosfet/6710545/
Download datasheet and compare.

These might do for the diodes? http://uk.rs-online.com/web/p/rectifier/6387915/

Dont know what rs is like for postage

[sabre504]

Re: AG Neovo X-17A

Hi Selldoor
as i said was hoping someone would have done one to confirm that it is the right one as i cant read all the part nums .
Think i will just get one and see how it goes as got nothing to lose
Paul

[selldoor]

Re: AG Neovo X-17A

I think that will be fine the important bit is there - the RSS050 and in that encouraging report you posted they mention it as well. ( The other numbers are just manufacturer info batch no/production date etc.

[sabre504]

Re: AG Neovo X-17A

Hi guys have ordered the parts i need from RS so will update when i have fitted them
Thanks for help so far
Paul

[sabre504]

Re: AG Neovo X-17A

Hi
right i have changed Q801 both diodes and ZD801

Q801 now a TCP8104
Source volt = 12.3v
Gate = 11.9
Drain = 1.11

U801 is a AIC 1578ps

pin volt

1 12.38
2 12.38
3 8.50
4 8.50
5 GND
6 11.00
7 12.38
8 12.38

D801 8.43 v in 1.11v out
ZD801 1.11 v in 00 v out


I suspect U801 may be at fault

PSU tested ok
Lamps ok
Inverter tested ok

Any ideas welcome

[jetadm123]

Re: AG Neovo X-17A

Is the output voltage of pin 6 a steady 11 Volts? Pin 6 is the mosfet drive output of the AIC1578. It's outputting a square wave, which drives the gate of the mosfet. Therefore, depending on the frequency, I would expect you to see a small or at least a fluctuating output at pin 6.

[sabre504]

Re: AG Neovo X-17A

Hi
It sits steady at 11

[jetadm123]

Re: AG Neovo X-17A

I guess I'm a little confused. Originally, Q801 was a RSS050. You now have substituted a TCP8104 in place of it? I can't seem to find a datasheet for the TCP8104?

[sabre504]

Re: AG Neovo X-17A

Sorry my error
TPC8104