Sir Posty07 . . . . .
To err is human
. . . . . . .
and BOY ! ! !
. . . . . are you human !
The immediate area in which you are kadiddlewhomping around in, is being in the circuit domain of the . . . . . sub power supply . . . . e.g.
JW5068 . . . . . Power Supply Circuit
It takes a portion of the FULL laptop power supply voltage and then down converts that full voltage
to a HEFTY 8 amp or more, as a separate lower voltage supply.
HOW TO READ THE FOIL . . . .
Bottom right corner, I see only see the visible P of probably what is a PLxxx designation.
Trace that lighter blue resist covered foil, downward and to over to the left , where it widens and initially passes to the other board sides foil thru 7 or so via holes and then two brown 0.1 ufd monolithic ceramic capacitors ***** provide bypass into the other foil pad just above them, which is a ground plane with its 9 or so vias to the boards other side and that ground plane also makes a connection into the pins 7-8 grounds of the JW5068.
***** ( The soldering installation of those caps closest end caps is APPALLING ! )
Now, in continuing with our light blue main full power trace to the left towards the PU501 area, it then connects with another minor ceramic bypass capacitor and has vacant pads above it for another, and FINALLY gets to its destination of the main power input pins of the JW5068
as 2-3-4-and 5.
Now what I would REALLY want to see, is the removal of ALL of that solder, BLOB to see what is being underneath it.
BECAUSE I see no need for there being a ferrite bead in circuit there unless they were wanting to be taking some of this FULL supply voltage off from this power trace foil and feeding it thru a ferrite bead for isolated EMI and RFI suppresion, to then pass that power off to feed another completely different circuit..
If so, one end of the beads end connector would be connected to this power buss foil area, while the OTHER connector end would have to be connected into a cut out and isolated pad, that uses a via to pass thru to the other board side. as I am seeing no routing out foil or an associated via being on this side of the board . . . . I am just seeing your very beeeeeeg solder / island. . . . . and some errant tiny solder droplets / splashes
Your small ferrite bead isolator should look like this . . . .
Now, can you initially get a well tinned soldering iron and invert the board an look up to that solder island and place the tip to it and let it melt and let gravity drain that solder down and onto your tip . . . doing it multiple times until minimal solder is left, and then use rosin flux and wick to get all of the remaining solder build up.
Follow up with an acid brush soaked in alcohol for a flux clean up.
Now . . . is there any foil routed out for isolation of the output end of this ferrite bead isolator ?
SUB SUPPLY OPERATION . . . . .
What you might check out after your power up of the unit, is the voltage output of that JW5068
supply and monitor it with a voltmeter connected to the aforementioned ground plane and the + meter probe going to either the pin 14 of
. . . or access might be made easier at the right end of the L1 ringing inductor, as is being the large, gray rectangular pot core at the 2 o'clock position from the JW5068
OR, I think that the filter capacitors for that supply are being the 3+ large monolithic block, high capacitance yellow ceramic capacitors, being located just above it.
Is the voltage being stable, BTW . . . what voltage level is it being ? or does it tie in to a related change just before the unit goes down ?
ON PAGE RE-REFERENCING TO PRE HOSTED BOARD IMAGE . . . . .
I've done some digging and it appears to be a ferrite bead, 80ohm impedance (specifically fbma-l11-800lma50t)
Care to SHARE info . . . . . as you haven't even given us the damn BRAND as well as its MODEL . . . also, possibly even a link to its SVC manual if having already found that specific part #.
Thaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaasit . . . . . . . . . . .
73's de Edd . . . . .
I used to think I was indecisive. . . . . . . . . . . . . . . .but now. . . . . . . . . . . . . . . . . .I’m not so sure.