LCD

Liquid Crystal Display

driving LCD

http://www.goldenviewdisplay.com/driving_LCD_display.html

http://www.pacificdisplay.com/lcd_multiplex_drive.htm

http://ww1.microchip.com/downloads/en/AppNotes/01428a.pdf

http://awawa.hariko.com/avr_lcd_drive_en.html

http://eewiki.net/display/microcontroller/Basic+LCD+Example+for+Xmega-B1

http://aardvarklabs.wordpress.com/

PCF8576 – Universal LCD I2C driver for low multiplex rates

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backplane

bias configuration

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Common and segment waveform static display

An AC voltage needs to be applied to the SEGMENT and COMMON. For a static display, there are only two levels for the voltage that are applied. These levels,which are driving the LCD, are called bias voltages. Astatic LCD wave will look like a square wave.

In next example, SEG0 is on and SEG1 is off, and both are connected to COM0 :

 

The advantage of this simple configuration is that itgives the best contrast. The disadvantage of this configuration is that the number of pixels that can be drivenis limited to the number of SEGMENT pins. To drive more pixels, more pins are required and there will be more connections from the board to the LCD glass.

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