BenQ Q7T3-FP737S, Service Manual

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Q7T3-FP737S Dual function LCD Monitor Service Guide
Circuit Operation Theory
3
Confidential
(a) Circuit operation theory:
A basic operation theory for the interface board is to convert input signal into digital RGB .
Analog RGB signal is converted to digital signal through ADC. DVI-D signal is converted
through TMDS receiver. The microprocessor Mst8131B receives video data and optimizes the
image automatically. It also supports input source selection, 16 color from a 64k palette bitmap
O S D , a n d k e y p a d c o n t r o l l i n g . T h e o u t p u t d a t a a r e s e n t t o L C D m o d u l e .
(b) IC introduction:
1.) DDC (Display Data Channel) function: We use DDC IC to support DDC/2B function. DDC data is
stored in 24C04(EEPROM). Those data related to LCD monitor specification. PC can read them by
“SDA” and “SCL” serial communication for I
2
C communication for DDC2B.
2.) Mst8131B IC: There are A/D, Scaling, OSD, MCU functions in the Mst8131B IC. Scaling IC is
revolutionary scaling engine, capable of expanding any source resolution to a highly uniform and
sharp image, combined with the critically proven integrated 8 bit triple-ADC and patented Rapid-lock
digital clock recovery system. It also support detect mode and DPMS control. MCU control unit, it
controls all the functions of this interface board, just like the OSD display setting, the adjustable items,
adjusted data storage, the external IIC communication, support DDC2B.
3.) EEPROM: We use 24C04 to store all the adjustable data and user settings.
And use 24C02 to store DVI EDID data.
4.) MTV312M64: To stored the source code which is accessed by MCU to run program.