Philips 15MF605T/17, Руководство по обслуживанию

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Magnavox LCD TV
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Circuit Description
Tuner & sound decoder deviation.
3. Function description:
MM tuner is used to receive RF wave and output CVBS and 2nd IF signal. CVBS is to video decoder
(SAA7119) for color process, 2nd IF is to sound decoder (MSP34x5) for audio process. The tuner control is via IIC ex. channel tuning.
For different TV system, tuner and sound decoder have diversity as above.
Standard TV input (Tuner, S-video, CVBS, SCART) is processed by SAA7119, But YPbPr, SDTV and HDTV(480i, 576i,
480p,576p,720p,1080i), is done by scaler MST51512L/502L ADC. But the signal is still link to SAA7119 if PIP (video in graph) function
is requested. Then all YPbPr signal processed by SAA7119 could be the PIP video source. (* May use down sampling in HD0)
MV protect is decoded by scaler.
Video decoder SAA7119, is in charge of color decoding, could support PAL, NTSC and SECAM world wide
system. Compare to SAA7118, SAA7119 improve some picture quality, like V-chip CC I2C read-back, LTI, CTI, skin tone
correction(see task A), also the HD0 is supported, so if F1 need PIP function then the The
Teltext function is for WE model, need a extra IC SAA5360. CVBS input, R/G/B, FB, out. Due to the SAA5360 request input signal
1Vrms and only one input channel, so the CVBS input source is from SAA7119 AOUT (CVBS out with 1Vrms). The R/G/B FB output
into SAA7119 by AI22/AI32/AI42, and AI44 could overlay on any video source.
Sound decoder MSP3415/45 is responsible to sound decode of tuner 2
nd
IF. It has one 2nd IF, two selectable audio sources input.
And one loudspeaker, one scart out. Due to the input port limitation, a MUX is added for AV source select( PC audio in is fix in SC1). If
the post audio amplifier is gain fixed type then the volume adjust will be on MSP34x5.
Scaler MST51502L/51512L besides scaling function, PIP, 3D de-interlacer, color enhance are major feature.
Even de-interlacer is not so good but for static picture is enough to avoid image sticking.
In America market, to avoid patent issue, two SDRAM is necessary for graph frame buffer. But in else region one SDRAM is
enough. Of course, if no PC mode in spec, then one SDRAM for all model.
The scaler structure limitation, the PIP source only from video port , 8 bits or 16 bits. The sub window /PIP size can enlarge to half
screen.
MCU, NT68F632AL, is 128K flash ROM inside. Power control, RC5 I/O, and key function all done by here.
All chip communication is by IIC (SDA/SCL), and ISP is via DDCIIC, but if PC mode un-supported, then a reserved 6pin connector is
for same application.
WE NAFT AP China
1601 Tuner FQ1216MK3 FQ1236 FQ1216 PN FQ1256
3139 147 18291 3139 147 18351 3139 147 20401 3139 147 20131
7101 Msp Msp3415 Msp3445 Msp3415 Msp3415
9322 194 13671 9322 194 12671 9322 194 13671 9322 194 13671
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