XOCECO LC-42T17, Service Manual

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PW218 (N601), after the above process the finally selected way will be set to X300 earphone socket
after under the control of volume, treble and bass which is finished by R2S15900 (N301), the
earphone socket has the switching function, when earphone is plugged, sound will be sent to
earphone amplifier NJW1109 (N302), then sent back to earphone socket after power amplification.
If earphone is unplugged, sound will be sent to sound amplifier TPA3008 to do amplification and
then sent to speaker.
Image parts:
Video signal of the tuner will be sent to AV switch box M52797 (N400), video signal of AV1 and AV2
will also be sent to M52797 (N400) at the same time, two groups of video output will be obtained
after switching, one group of video output together with its audio output will be sent to AV_OUT
terminal to treat as AV OUT. The other group of video output together with other video signals such
as S-VIDEO, YpbPr1, YpbPr2 and VGA will be sent to PW2300 to do video decoding or AD
transformation, then output 24bit digital RGB signal and some corresponding synchronous signals.
Items such as 3D comb filter, channel switching, 5 lines Y/C separation and color decoding etc. are
primarily done by PW2300. 24bit digital RGB signal and some corresponding synchronous signals
outputted by PW2300 will then be sent to PW218 (N601). HDMI signal will also be sent to AD9398
(N101) to de decoding and output 24bit digital RGB signal as well as some corresponding
synchronous signal, which will be sent to PW218 (N601). PW218 is a new generation chip of
Pixelworks, which has ability to deal with images, 24bit digital RGB signal and some corresponding
synchronous signals outputted by AD9398 and PW2300 will be sent to this chip to deal with images.
The chip has functions such as converting from interleaved into line-by-line and image
enhancement etc.. PW218 has SCALER function which can do format conversion towards different
input formats so as to meet the format needs of the screen and finally output 24bit RGB signal. The
interface standard of PDP screen is generally LVDS (low voltage differential signal), so the digital
RGB signal outputted from PW218 is needed to send to converting interface chip N6 DS90C387 of
LVDS to obtain LVDS signal, then it will be sent to the screen. PW218 is also the main CPU, its
programs are stored in periphery device flash N701, and software upgrade through RS-232
interface is virtually upgrading the stored programs through PW218 towards N701.
Chief functions:
High definition 1080P LCD
16:9 wide screen
Support several kinds of HDTV wide voltage range, low standby power consumption (less than 1W)
One group of D-SUB, S-VSH (Y/C), RS232, AVOUT, HEADPHONE, HDMI, two groups of
YPbPr/YCbCr, AV.