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ViewSonic Corporation
24
Confidential - Do Not Copy
VA703b-4_VA703m-4
C, MTV512M
The MTV512M micro-controller is an 8051 CPU core
embedded device especially tailored for flat panel
display applications. It includes an 8051 CPU core,
768-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 in 44-pin PLCC package
FEATURES
• 8051 core, 12MHz operating frequency with
single/double CPU clock option
• 0.35um process; 3.3V power supply
• 768-byte RAM; 64K-byte program Flash memory
• Maximum 6 channels of PWM DAC
• Compliant with VESA DDC1/2B/2Bi/2B+ standard
• Dual slave IIC addresses; two H/W auto transfer
DDC1/DDC2x data for both D-sub and DVI
interfaces
• Watchdog timer with programmable interval
• Support external counters/timers, 1 & 2
• Single/double frequency clock output
• Two external interrupts, INT1 is shared with Slave
IIC interrupt source.
• Maximum 4 channels of 6-bit ADC
• Flash-ROM code protection selection
• 44-pin PLCC package
D. INVERTER
In order to drive the CCFLs embedded in the panel module, there is a push-pull inverter to convert by the controller. from
input 24V up to hundreds of AC voltage output peak to peak.
The inverter is formed by symmetric in order to drive the separate lamp modules.
The input stage consists of a PWM controller, push-pull inverter, and switching MOSFET to convert DC input into AC output.
The output stage consists of a tuning capacitor, transformer, and push-pull MOSFET pair to boost AC output up to hundreds of
voltage peak to peak.
And one resister is serial to lamp for output voltage feedback.
There are two signals which control the inverter come from system to turn on the inverter and control brightness. Logic “low”
level which send to U901 is turn on the inverter.
BL-ADJ signal control brightness by DC level which was integral from PWM signal.
Summary of Contents for VA703b-4
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