10 Feb
2011
10 Feb
'11
12:20 p.m.
I think I know what you mean now. That TA 7259 is the chip underneath the
large brown clip/cover at the front of the drive. I'm not sure how to
Yes. That 'clip' looks to be a piece of copper sheet acting as a
heatsink. The standard drive doesn't have it, perhaps the Apple drive
with its variable speed ssytem caused the driver chip to run hotter or
something. Iwoudl guess it's soldered to the 2 tabs of the TA7259 chip.
These tabs are the electrical ground conenctions to the chip and also
connect ot a metal plate inside the backage that the silicon chip itself
it mounted on, to carry heat away from the chip.
Do you have the TA7259 datasheet? It's on datasheetarchive
(http://www,datasheetarchive.com/), just type'TA7259' in the search box.
remove the latter though? I seems solidly glued in
covering the pins of the
chip. If I could remove this, I could measure the signals on these pins
when I tap the switch (thereby fooling the drive into thinking a disk is
present).
Or do you need to remove the motor, switches, plugs and then slide the motor
PCB out towards the rear until it's clear of that clip/cover. Thinking
about it, that's probably what's needed. In that case, it won't be so easy
to test as everything will be in bits.
No, the spidnle motor certainly comes out upwards. it has to. The
speindle bearing ftis in a hole in the chassis casting. I would try
removing the sensor arms as I said last nigth and taking out the 2
scress. See if the mtoro is free, if not, see what is holding it. The
heatsink will come out with the motor.
-tony