FUJITSU Semiconductor Controller MB89950/950A - Manual (Page 250)

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CHAPTER 12 LCD CONTROLLER/DRIVER
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Display RAM
This 42 x 4-bit block of RAM controls the segment output signals. Its contents are automatically read out to
the segment outputs in synchronous with the timing of the selected common signal.
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Prescaler
The prescaler generates one of the 4 frame frequencies according to the LCD control register setting.
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Timing controller
This block controls the segment and common signals based on the frame frequency and LCD control
register settings.
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V/I converter
This circuit generates alternating current waveforms from the voltage signals it receives from the timing
controller to drive the LCD.
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Common output driver
This block contains the drivers for the LCD common pins.
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Segment output driver
This block contains the drivers for the LCD segment pins.
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Voltage divider (optional)
This voltage divider is used to provide the divided LCD driving voltage. The voltage divider can be
connected externally.