LG 42LH40 Series, Руководство пользователя

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There are three types of Main Power switch used in LG televisions. This set utilizes Type 1.
Type 1:
Shuts off AC to the Power Supply.
Type 2:
Opens ground to the front IR board. (Stand-By 5V Remains, the Main board stays alive).
This prevents any activity of the IR or the Key Board. When the Switch is opened, a line called
Power Key pulls up high when ground opens. When the switch is closed, this same line called
Power Key feeds back to the Microprocessor and the Micro. Turns on the Power.
Type 3:
Opens ground to the front IR board. (Stand-By 5V turns off, the Main board is dead).
This prevents any activity of the IR or the Key Board. When the Switch is opened, a line called
Power Key pulls up high when ground opens. This line feeds back to the Main board and from
there it routes to the Power Supply. The high tells the Controller chip to turn off STBY-5V.
When the switch is closed, this same line called Power Key now goes high and feeds back to
the Power Supply and tells the controller chip to turn STBY-5V on.
Power Supply (Main Power Switch Type 1) Location
Power Supply (Main Power Switch Type 1) Location
Off
On
If the TV won’t come on, be sure to check the Main
Power Switch before assuming a failure has occurred.
This switch breaks AC to the SMPS.
MAIN POWER SWITCH LOCATION
TYPE 1
(Bottom Right Side viewed from front)
July 2009 LCD DV 42LH40
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