Front (Ir, Intelligent Sensor And Power Led) - LG 55LW5600 Troubleshooting Manual

FRONT (IR, INTELLIGENT SENSOR and POWER LED) SECTION
The Intelligent Sensor and IR board (located on the bottom left as viewed from the rear) contains the IR
(Infrared Remote Sensor) and the Intelligent Sensor. This board also has the Soft Touch Key Board.
The IR board receives it operating B+ pin 6 from the Main P901 (STBY 3.5V).
The IR (Infrared) remote receiver can be measured (1.48V) at pin 9 of connector P901 on the Main board in
Stand-By. During run pin 9 reads (1.47V).
The IR pulses (2V p/p) are sent to the Main board and on to the Microprocessor (IC602) via pin 16. The IR pulses (2V p/p) are sent to the Main board and on to the Microprocessor (IC602) via pin 16.
The Front Power LEDs are controlled by different Clock and Data lines which communicate with the LED
Driver IC U1. These clock and data lines are from the Main board P901 pins 14 and 15 which are only active
when the Power is turned on or off.
The Soft Touch Keys are part of the IR board. Key 1 (pin 4) and Key 2 (pin 5) are output From Pat P901 on
the Main Board, then to the Microprocessor 25 and 26 lines.
The Intelligent Sensor communicates with the Micro Processor IC602 pins 3 & 4 via clock and data lines
EEPROM SCL and EEPROM SDA arriving on connector P901 pins 1 and 2 on the Main board EEPROM_SCL and EEPROM_SDA arriving on connector P901 pins 1 and 2 on the Main board.
The Intelligent Sensor circuit receives it's operational voltage when the set turns on via pin 11
(3.3V_Normal).
1
Front IR and Soft
Touch Key Board
p/n EBR72671301
To Main Board
Plastic Cover. Wire routing.
July 201 1 LCD TV 55LW56000
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