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Appendix. Checkpoints for module-related defects for UHD T-con less models (No screen / Sound Ok)
Checkpoints for the power supplied from Main B/D to Module
- The voltage of the 5 points may be different for each module, but it must be within the voltage range as shown in the table below.
- If there is no power when it's connected to the Module, remove the cable connected to the Module and check.
(If the module is defective, the power may be lost because of the Module, not because of the Main B/D)
① VCC1.8
①
②
② LS-VGL
<Back part of PCB>
③ HVDD
③
④
④ VDD-EPI
No
Pin Name
Voltage range
1
VCC1.8
1.8V ~ 1.9V
2
LS-VGL
-20V ~ -4.5V
3
HVDD
VDD-EPI / 2
4
VDD-EPI
13.8V ~ 20V
5
VGH1
20V ~ 45V
※ To be improved by applying additional TB (Test Point) on the
- No need to separate Main B/D from Module to measure the voltage of the back part of Main B/D,
Appendix. 1 / 1
[E.g. Main B/D of 75QNED966QA T-Conless model]
⑤ VGH1
⑤
After removing the Main B/D screws, flip the PCB over and measure the JP (Jig Po
Note
HVDD uses half the voltage of #4 VDD
front part
of PCB (for new models to be launched after 2023 )
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Only for training and service purposes.
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