Eiki LC-XNB4000N, Service Manual

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Level 2 Structure diagram
The projector consists of the main board, keypad board, power PFC board, ballast board,
door interlock switch, sensor board, thermal break sensor board and IR receiver board.
Main Board is mainly composed of an image processor, EEPROM, flash memory, Thermal
detective circuit, FANs driver circuit, temperature sensing circuit, Audio control circuit, LCD
video signal processing generator, LCD panel driver circuit and low power management
circuit.
Keypad Board consists of 9 key-buttons and 2 LEDs indicator.
Power supply circuit consists of AC line EMI filter, Power Factor Correction circuit.
Ballast Board consists of Lamp synchronization circuit, Lamp lit feedback circuit, and
power control circuit.
The Image Processor (chipset is PW190) also known as “Scaler”, which indicate its main
function, expand or down size the digital picture from digital input or ADC to a fixed size
digital image output. The CPU which controls the whole system is embedded inside the
Image Processor, there is also a Real Time Operating System which incorporates with the
CPU as hardware layer interface.
One of input signal is HDMI of an EP9853 HDMI receiver, which is totally compatible with
the HDMI specification, and supports digital output to Image Processor.
Others input signal are analog RGB format, Video, S-Video input and YPbPr input, which
comes from the standard VGA D-SUB, Video, S-Video and YPbPr connectors, the signal
input to ADC converter, which output RGB digital data stream to Image Processor.