T-Con Section - LG 42LH50 Training Manual

T - CON (TFT DRIVE) PWB
T - CON (TFT DRIVE) PWB
LCD Controller Board
The T-Con IC UC1 receives from the Main Board at CN1 12 Bit and CN2 12 Bit LVDS
Signals (Video) which it processes into TFT Drive Signals. It delivers its output signals
through connectors CN4 and CN5 to control the LCD Panel.
12V is supplied to the T-Con Board on connector CN1 from the Main Board
(easily measured at fuse F1).
Diode LD1 is a boot up indicator and is helpful in troubleshooting as a quick indication of a
loss of supply and or a Boot up problem. The main purpose of LD1 is to aid in the firing of
the EEFL backlights when room light is minimum. It helps to excite the selenium in the
EEFL lamp which is highly sensitive to Blue light. Once this lamp fires, it helps to excite the
others.
There is one regulator that creates 1.19V developed at pin 2 (Center Leg) of U11.
U5 is a DC to DC converter IC which develops the Panels driver voltages. 16V, 3.3V, -5V
and 26V.
These voltages can be read at the ribbon connector or at test points on the board.
2009 FALL LCD DV 42LH50
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