Voltage Measurement; Preconditions – Dc/Dc Check; Panel Id Check And Modify; Voltage Chart - Philips 22PFL5557/V7 Service Manual

4. Voltage Measurement

INFO:
All tests and measurements mentioned hereafter have to be carried out at a normal mains
voltage (220 ~ 240 VAC),
All voltages have to be measured with respect to ground, unless otherwise stated,
All final tests have to be done on a complete set including LED panel in a room with
temperature of 25+/-7°C,
The White Balance (color temperature) has to be performed into subdued lighted room after
at least 1 hour of warm-up/burn-in. This is applicable for both Alignment and Picture
Performance evaluation at OQA in order to be set free of any temperature drift (colorimetry vs
time).
Preconditions – DC/DC Check
1.1.
Before power on, please check the board according to the relevant block diagram and
circuit diagram, and make sure that no serious error should destroy the board. For
example, the output of DC/DC and LDO should not be shorted to ground. Supply a suited
voltage and power on, then check the voltage according to the relevant block diagram ,
circuit diagram and voltage spec. the error should less than 5% .For example, the voltage
for main chip(3.3V, 2.5V,1.8V,8V,etc.), the voltage for DDR2 , the voltage for amplifier ,etc.

1.2. Panel ID check and modify

There is different ID stored in the NVM depended on different Panels.
It can be checked and
modified in Factory menu -> SW INFO.
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