Sharp QD-101MM, Руководство по обслуживанию

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3.VIDEO INPUT CIRCUIT
Fig. 4 shows the block diagram. Circuit diagram is shown in VIDEO CIRCUIT.
This unit automatically switches the circuit corresponding to the composite video signals of
NTSC, PAL and SECAM. The composite video signal and S-Video signal input to the decoder
are first converted into the 8-bit digital Y,UV signal, and is output as the 8-bit digital RGB from
the RGB converter(IC601).
Horizontal sync signal CSHSYNC, vertical sync signal CSVSYNC, ODEV signal and system
clock LLC2 are simultaneously output from the decoder(IC600), and are used in the process
circuit in the rear step.
Controls of brightness, color and tint, and the initial setting of decoder and RGB converter are
sent from MPU by the I
2 C bus.
Fig. 4 Composite Video / S-Video Input Circuit Block Diagram
4.AUDIO INPUT CIRCUIT
Fig. 5 shows the block diagram of the audio input circuit. Circuit diagram is shown in AUDIO
CIRCUIT.
The audio signal input to the audio input terminal is inputted to the audio level controller, and
is controlled to the level which corresponds to the volume signal output from MPU.
The output enters the mute switch circuit in the next step, and the audio signal is turned on and
off corresponding to the SMUTE signal which is output from MPU.
CSHSYNC
CSVSYNC
LLC2
ODEV
RGB 8bit
Y,UV/RGB
CONVERTER
Y,UV
8bit
CONTROL
I C BUS
COMPOSITE VIDEO
SDA,SCL
DECODER
CN600 IC600
SAA7110
IC601
SAA7192
21
45~50
53~62
29
31
42
32 63
64
65
26
38,41
30
40
16,17,
20~25
30~34,37~39
40~47
48~50,53~57
5,6
CN601
17,19
S-VIDEO
2