Mitsubishi Electric LT-2220 Service Manual page 24

MODELS: LT-2220 / LT-2240 / LT-3020 / LT-3040 / LT-3050
(D)IC2J1 : TMDS receiver IC with HDCP (Sii907B : SiliconImage)
In this IC, the input signal is processed based on EIA-861A. Inputs from a TMDS-Interface are
converted into a RGB analog signal. HDCP and HDTV resolutions are supported.
When no DVI signal is input, it changes to standby mode automatically and power consumption is
lowered. The LCD panel specification is for input signals whose vertical sync signal is 60Hz. The
outputs of this IC include separate horizontal and vertical sync signals.
(E)IC201 : Analog-switch IC with LPF (SM5301A : NPC)
In this IC, the component signal (Y, Cb, Cr) from IC204 or DVI signal (R,G,B) from IC2J1 is chosen
by the select signal and outputted.
Select signal MUXSEL is controlled by the MCU.
(F) IC202 : Sync separate IC (LM1881M : National Semiconductor)
Used for Component input.
This IC separates the composite H and V sync signal from the composite video signal
The composite sync signal is sent to IC203 (Sync select IC).
(G) IC203 : Sync select IC (HD74LV157: Hitachi)
In this IC, the composite sync signal from IC202(for component) or Separate sync signal from
IC2J1(for DVI) is chosen by the select signal and outputted.
Select signal MUXSEL is controlled by the MCU.
The output from this IC is sent to IC400 (Signal processor IC) in order to remove the
vertical sync signal and output the separated horizontal sync signal. The horizontal sync signal is
then routed to IC205 (Analog-to-digital conversion IC).
(H) IC205 : Analog-to-digital conversion IC (AD9883AKST-110 : Analog devices)
The Component video (YCbCr / RGB) or DVI inut is converted into a digital signal (8 bits
each) from an analog signal. Besides digital conversion this IC performs the following:
Contrast adjustment for Component or DVI
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brightness adjustment for Component or DVI
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This IC is controlled by register control of IC 205 via 3.3V IIC-bus.
This IC's output is sent to IC500.