July 2010 LCD TV 47LE8500

85
FRONT (IR, INTELLIGENT SENSOR and MOVING LED) SECTIONFRONT (IR, INTELLIGENT SENSOR and MOVING 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 connects with the Soft Touch
Key Board and the Center LG Logo board. The Center LG Logo lights after power on and the picture
appears. Then dims down in about 2 seconds. At power off, it does the reverse.
The IR board receives it operating B+ via CON1 pin 6 (STBY 3.5V).
The IR (Infrared) remote receiver can be measured (1.57V) at pin 9 of connector CON1 or P8200 on
the Main board in Stand-By. During run pin 9 reads (1.54V).
The IR pulses (1.6V p/p) CON1 pin 9 are sent to P8200 on the Main board and on to the
Microprocessor (IC8101) via pin 16.
The Intelligent Sensor communicates with the Micro/Video Processor IC900 BCM Chip via clock and
data lines SCL1 and SDA1 arriving on connector CON1 from P8200 pins 1 and 2 on the Main board.
The Front Power LEDs are controlled by these same Clock and Data lines which communicate with
the LED Driver IC U1 on the Soft Touch Key board.
The Key board is routed to the IR board via CON2 and output on CON1 Key 1 and Key 2 lines, (Key 1
pin 4 and Key 2 pin 5). Arriving at P8200 pins 4 and 5 on the Main Board.
Then to the Microprocessor 25 and 26 lines.
Leandro Palmeira
Downloaded From TV-Manual.com Manuals