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Faulty LCD CCFL Inverter

Hello,

I have a Samsung 193 19" LCD monitor that has a faulty CCFL inverter.
The SMPS and inverter are built together on the same PCB. The inverter
normally drives 4 CCFL's and it had a blown 4A fuse; so I changed the
fuse and it blew again. Closer inspection of the bottom of the board; I
noticed a 8 pin IC (MOSFET?) was burnt and shorted.

There are a total of four of these IC's. The other three tested OK and
I replaced all four bad 47uF caps near the IC's (some where high ESR).
I checked for shorts on the four HV transformer...there are none. The
cold cathode lamps are also fine.

Does anyone know what these IC's are and where they can be found? or a
possible substitute?

The numbers on the IC:
4600
AD3S45

They are the SSOP 8P package type.

Thanks!
 
D

Dave

There are a total of four of these IC's. The other three tested OK and

Does anyone know what these IC's are and where they can be found? or a
possible substitute?
Can you please outline the method you used to test these _UNKNOWN_ IC's?

I run into this type of problem all the time and boy, if I could test
something before I even knew what it was it would sure speed up my repairs!

Does it work on ALL IC's or only 8-pin ones?

Does it rely on a battery-powered tester you bought for the low low price of
$39.95 (just four easy payments of $9.99, batteries not included) on
late-night TV?
 
F

Franc Zabkar

Hello,

I have a Samsung 193 19" LCD monitor that has a faulty CCFL inverter.
The SMPS and inverter are built together on the same PCB. The inverter
normally drives 4 CCFL's and it had a blown 4A fuse; so I changed the
fuse and it blew again. Closer inspection of the bottom of the board; I
noticed a 8 pin IC (MOSFET?) was burnt and shorted.

There are a total of four of these IC's. The other three tested OK and
I replaced all four bad 47uF caps near the IC's (some where high ESR).
I checked for shorts on the four HV transformer...there are none. The
cold cathode lamps are also fine.

Does anyone know what these IC's are and where they can be found? or a
possible substitute?

The numbers on the IC:
4600
AD3S45

They are the SSOP 8P package type.

Thanks!

Could the device be a dual MOSFET?

Is there a CCFL inverter controller IC nearby? If so, I'd download its
datasheet and hope that the application diagram gives some clue as to
the identity of your device.

- Franc Zabkar
 
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