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malvern batsirai kaserera malvern batsirai kaserera is offline
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Default DVD Drive motor power

On Dec 20, 7:49*am, DA wrote:
responding tohttp://www.electrondepot.com/repair/dvd-drive-motor-power-136411-.htm

DA wrote:
Chas *wrote:
Working on a friends Goldstar GBV441 DVD/RW/CD/RW-VHS/RW unit.
The DVD motor does not spin.
*. . I did cut one wire on the DVD drive motor...it showed resistance..
Just
to be sure
(cheapo multimeter) *I ran 5 vdc (from a model RY controller) and the
motor
spun with no problems...


DVD spindle motors are usually brushless DC (BLDC) motors that would not
work by just powering them with DC - you'd need a driver IC that creates
the proper waveforms. So, my guess is that this deck has just a simple DC
motor instead? Otherwise the 5VDC trick wouldn't work. How many wires are
coming out of that motor?

The laser tracking
slide moves ok and the laser is illuminated. The spinner frane elevates
and depresses ok. *Everything seems to be working fine except the DVD motor
is not getting power.


I'm not familiar with the particular model but in those DVD drives I've
seen insides of, all motors (and also any solenoids) are driven by the
same IC. ROHM's BA5995FM would be one example (or others in BA68xx
series). It's a 28-leads HSOP28-M package (with a thick grounding/heat
sink solderable connector plate in a middle) that requires very little
extra components. In other words, if the motor does not spin and the motor
itself is OK, it's either the IC or the Hall-effect sensors (or whatever
other sensors there may be in the speed control feedback) - either way the
repair is very tricky because the faulty parts are the least serviceable.

I don't want to suggest it's necessarily your case but you may want to
look around for a 28+ pin driver IC that may be connected to the motor.
Then work your way from the motor (the best serviceable) down to the IC
(the least serviceable)

Post more info about the motor, I may be able to help more if it's type is
known.

Good luck!
-------------------------------------
*/_/
((@v@))
()::)
*VV-VV


If the dc motor is not turning,I will advise you to remove the motor
from the deck power it with external voltage source for about 4 to 5
minutes and return it.This is called dc excitation ,because, I believe
the magnets inside the dc motor are loosing their magnetic
properties .Hope this finds you well.If I may like to ask ,did you
measure the output voltage where the dc motor is connected?