Level 3 - Component Repair To Curcuit Boards; Theory Of Circuit Operation - BenQ VL3735 Service Manual

Level 3 - Component Repair to Curcuit Boards

Theory of Circuit Operation

1. Main Board
In the main board circuits, it contains Audio amplifier (TPA3100D2), AD converter (AD9883),
HDMI receiver (SII9011), Video decoder (SAA7117/AE), de-interlace with Scalar (PW318C).
1.1. Overview
1. The Main Board includes 3 input connectors. They are HDMI input, D-sub input, DVI
Audio input (L/R).
2. The Graphic port input includes (1) HDMI input connector, (2) PC input.
The HDMI input connector can accept digital RGB format signals. This input can support
VGA ~ XGA (60Hz) PC signals in DVI mode, and also 480p, 576p, 720p, 1080i, 1080p video
signals in HDMI mode.
The PC input connector can accept analog RGB format signals. This input can support VGA
~ XGA (60Hz) PC signals, and also 480p, 576p, 720p, 1080i video signals.
The Component can accept analog YPBPR (480i, 576i, 480p, 576p, 720p, 1080i) signals.
Because a HDMI decoder (SiI9011) is used, this LCD TV also can decode HDCP signals.
3. The Video port inputs (included Component YCbCr./YPbPr, S-video and Composite video)
will be processed by the video decoder (SAA7117), then processed by the de-interlace
processor (PW318).
4. Both graphic and video port signals will be processed by the scalar. The scalar will convert
input signals into RGB 4:4:4, 24-bit signals by downscaling or up-scaling.
5. Main board contained two "board to board" connectors. One is for video board connection;
another is for DTV board (reserved) connection. Video board connector is included
component signal, composite signal, S-video signal, audio signal (R/L), I2C and some GPIO
signals. DTV board connector is included component signal, composite signal, audio signal
(R/L, SPDIF), UART and some GPIO signals.
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