Service manual

ANALOG SIGNAL INPUT and EDID

This product uses the internal function of Mascot V (U1) as a signal detector in order to support separate SYNC.

The analog input Horizontal and Vertical Synchronal signals pass through the Schmitt trigger buffer U4 to stabilize

then input to

Mascot U1 pin38 VGA_VSYNC, pin39 VGA_HSYNC or pin40 SOGI and the image processing.

Then

Mascot will detect the signal type if it is separate SYNC, composite SYNC or SOG. MPU (U6) reads the

input signal type from IIC protocol and does the correct procedure to generate the proper signals to the whole

system.

24LC02 (U14) chip provide DDC1/2B¥ with Analog Plug&Play, and the DDC data format is EDID v1.3.

See FIG1-2.

FIG1-2

ViewSonic Corporation

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