4. Block Diagram
PB6100 DMD projector being using the SGA DMD Engine made by BENQ, it included
front end circuitry that digitizes and scaling processes for the input analog VGA and TV signals. As
shown, in figure below the front end circuitry consists of :
1. Frond end Circuitry
1.1
Power supply module include PFC and DC/DC portion. DC/DC portion provide 12V, 5V and
3,3V for whole system.
PFC
IGNITOR
POWER SUPPLY
Module
AC IN
DC to DC
EMI Filter
1.2 Pixelworks scaler(PW166) with x86 CPU, OSD and SDRAM is used for system control. It control
whole system operation and with crucial role of this system.(Include fan speed, inter-lock SW,....)
1.3 A/D-decoder(AD9883) is used for decoding VGA analog signal to digital signal(RGB 888) which
provide 24 bit true color resolution. It can accept SOG(sync on green) and composite signal for PC
input. It also support YPbPr signal.
1.4 The video decoder that process TV video signal input. The TV video signal support both of
composite and S-video input and output YUV format to scaler processor. The basic block as
following.
12V
Lamp Fan1
Lamp Power
Lamp Fan
For System
12V,5V,2.5V
Power Fan
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