ViewSonic Q9-1, Service Manual

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1.
WORKING THEOREM
A. Scaler
The RTD2023 is total solution graphics processing IC for LCD monitors with panel resolutions up to SXGA. It is configured with integrated 8-
bit triple-ADC/PLL, a high quality display processing engine, and an integrated output display interface that can support Dual / Single LVDS
panel interface format. To further reduce system costs, the RTD2023 also integrates intelligent power management control capability for
green-mode requirements and spread-spectrum support for EMI management. The RTD2023 incorporates the world’s first coherent
oversampled RGB graphics ADC in a monitor controller system1. The oversampling ADC samples the input RGB signals at a frequency that
is much higher than the signal source pixel rate. This can preserve details in the video signal that ordinarily would be lost due to input signal
jitter or bandwidth limitations in non-oversampled systems.
B. MCU:
The MTV512M micro-controller is an 8051 CPU core embedded device especially tailored for flat panel display application. It
includes an 8051 CPU core, a 768K-byte SRAM, 4 channels of 6-bit ADC,3 external counters / timers ,6 channels of PWM
DAC,VESA DDC interface, and a 64k-byte internal program Flash-ROM memory. of 6-bit ADC, and a built-in , It also includes two
IIC Slave B ports, supporting VESA DDC/CI for D-sub interfaces, and a Boot-Code-Free ISP (In System Programming).
4. Circuit Description
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nfidential - Do Not Copy Q9-1_Q9b-1