Samsung HPR4272X/XAC, Service Manual

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Circuit Description
13-26 Samsung Electronics
■
Troubleshooting the Drive Board
1) Y Buffer
- To check whether the Y Main board is properly working, check the operation of the Y Buffer first.
- Separate the connector of the Y Buffer from the Y Main board.
- Check OUTL and OUTH and confirm that the forward voltage reduction is between 0.4V ~ 0.5V.
UP - CN5407 1~10pin - OUTH / 11~33pin - OUTL
LOW - CN5507 50~41pin - OUTH / 40~17pin - OUTL
- In addition, the resistance between the points must be higher than a few k
Ω
.
OUTL OUTH
CN5501
- Panel
CN5502
- Panel
CN5503
- Panel
CN5504
CN5506
CN5402
- Panel
CN5403
- Panel
CN5401
- Panel
CN5406
CN5404
OUTL
OUTL
OUTH : 2 pins of bottom side.
OUTH : 2 pins of
upper side.