D
Derek
Guest
Hello everyone,
I have a dell inspiron 8100 laptop, with a 15 in. active matrix TFT
display ("UXGA" or ultra xga, capable of 1600x1200 resolution). About
6 months ago, the Sharp LCD on this laptop started displaying a
vertical blue line (single pixel width) about an inch and a half from
the right edge of the screen. Since the laptop was no longer under
warranty, I did a little web research, and discovered that the "flex
cable", which presumably carries the data bus, reset lines and so on
(there's a separate power cable), had a tendency to malfunction, since
it had a 90 degree "twist". Unfortunately, reseating this cable, and
replacing it did not help. However, I did discover that applying
pressure to one of the dark plastic (it almost looks like film) areas
on top of the lcd, near the always-on line of pixel, tended to fix the
problem. These film-like plastic sheaths seem to be adhered to PCBs on
the rear of the LCD, but they seem to be non-conducting, and I'm
unclear as to what their purpose is - there is an elliptical metallic
area at the centre, and there are sever. They're labeled STAB0, STAB1
(through stab 12 or so - there are horizontal versions as well,
leading me to believe that they're associated with the row/column
control lines for the TFTs) and so on. I cannot find a schematic for
this LCD on the web, unfortunately. I've used LCDs with attached
controllers (the HD44780 for instance) for microcontroller projects,
but those tended to be relatively simple, with an 8 bit data bus and a
few other lines such as register select, r/w and so on, so I'm rather
lost when it comes to this sort of display
Since the problem first
appeared, it has worsened, and there are now 10-12 lines which are
"always on". I don't believe the actual transistors are dead, or that
there's a problem with the display itself, but it seems to be a loose
contact of some sort. Any thoughts or anecdotes of how this sort of
problem can be fixed would be appreciated!
I have a dell inspiron 8100 laptop, with a 15 in. active matrix TFT
display ("UXGA" or ultra xga, capable of 1600x1200 resolution). About
6 months ago, the Sharp LCD on this laptop started displaying a
vertical blue line (single pixel width) about an inch and a half from
the right edge of the screen. Since the laptop was no longer under
warranty, I did a little web research, and discovered that the "flex
cable", which presumably carries the data bus, reset lines and so on
(there's a separate power cable), had a tendency to malfunction, since
it had a 90 degree "twist". Unfortunately, reseating this cable, and
replacing it did not help. However, I did discover that applying
pressure to one of the dark plastic (it almost looks like film) areas
on top of the lcd, near the always-on line of pixel, tended to fix the
problem. These film-like plastic sheaths seem to be adhered to PCBs on
the rear of the LCD, but they seem to be non-conducting, and I'm
unclear as to what their purpose is - there is an elliptical metallic
area at the centre, and there are sever. They're labeled STAB0, STAB1
(through stab 12 or so - there are horizontal versions as well,
leading me to believe that they're associated with the row/column
control lines for the TFTs) and so on. I cannot find a schematic for
this LCD on the web, unfortunately. I've used LCDs with attached
controllers (the HD44780 for instance) for microcontroller projects,
but those tended to be relatively simple, with an 8 bit data bus and a
few other lines such as register select, r/w and so on, so I'm rather
lost when it comes to this sort of display
Since the problem firstappeared, it has worsened, and there are now 10-12 lines which are
"always on". I don't believe the actual transistors are dead, or that
there's a problem with the display itself, but it seems to be a loose
contact of some sort. Any thoughts or anecdotes of how this sort of
problem can be fixed would be appreciated!