Samsung PDP4298ED, Service Manual, Page: 60 / 102

Circuit Operation Description
Samsung Electronics 5-41
4-4 Board Drawings and Appearance
1) Logic Main Board
Figure 1. Appearance of the Logic Main Board
GND1
TP13
Figure 2. Connecting probe 1 of the oscilloscope
TP13
GND1
4-5 Logic Main Board Switch Operation
1) Internal Pattern: Set SW2001 No.2, and 4 to OFF(DOWN), No.3 to ON(UP).
2) External Pattern: Set SW2001 No.2, and 4 to ON(UP), No.3 to OFF(DOWN)/
❈
Manipulate the switches to the internal pattern for board inspection.
❈
Ignore SW201 No.1.
4-6 Board Inspections
1) All logic main boards should be completely inspected.
2) Visually inspect the part-soldering state of the entire board.
3) Set the instruments for waveform inspection.
!
When a linear power supply is used, set the output voltages to 5V or 3.3V in advance.
When a SMPS is used, ensure that the output voltages are 5V or 3.3V.
@
Set the oscilloscope to 4ms/div and 2V/div.
Connect PROBE 1 as shown in the following figure and set it to TRIGGER.
Perform the test by capturing the waveforms from each point with PROBE 2.