ViewSonic N3250w-1L, Service Manual

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MT8293 has 3 I2C interfaces.
LCD Controller IC use the CSDL/CSDA interface to access MT8293 registers.
MT8293 use KSDL/KSDA interface to read HDCP key from the EEPROM.
HDMI transmitter use DSDL/DSDA to access MT8293 HDCP related register.
HDMI Transmitter will pull high HDMI_PLUG_POWER (pin 18 in connector) when the
cable is connected. LCD Controller will pull high HDMI_HPD (pin 19 in connector) to info
the HDMI transmitter that the receiver is ready. The HDMI transmitter sends the video &
audio to MT8293 via 3 Data TMDS pairs & 1 CLOCK TMDS pairs.
Digital video signals are directly output from the MT8293 and then transfer them to the
MT8202 for advanced processing.
D. Audio
MT8202 incorporates a on-chip audio processor decodes whole world standard audio signals
from tuner with lip sync control, delivering high quality post-processed sound effect to
customers. Audio interface accept analog audio signal from Tuner, e.g. SIF or AF. It also
includes preprocessing circuit to filter the noisy audio signals. Audio decoder will decode the
BTSC, and output best sound with enhanced 3D surround post-processing.
The AD12250 converts stereo single-ended analog input signals into 24-bit I2S digital audio
data through on-chip anti-aliasing filter, multi-bit
Σ
-
Δ
modulator, decimation filter and
high-pass filter which removes dc offsets. External analog audio signal , such as AV, S-video,
etc. is directly fed into AD12250 via a audio switch and converted to I2S digital audio data.
Digital audio, such as HDMI , have decoded by MT5351 and MT8293, is converted to I2S
digital audio already. The I2S digital audio data is decoded and processed by MT8202, and
then be delivered to AD8256 for audio amplifying.
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N3250w-1L
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