HD44780 Hitachi Semiconductor (acquired by Renesas), HD44780 Datasheet - Page 35

• Manufacturer Part Number: HD44780
• Description: Dot Matrix Liquid Crystal Display Controller/driver
• Manufacturer: Hitachi Semiconductor (acquired by Renesas)

Since five segment signal lines can display one digit, one HD44780U can display up to 8 digits for a 1-line
display and 16 digits for a 2-line display.
The examples in Figure 19 have unused common signal pins, which always output non-selection
waveforms. When the liquid crystal display panel has unused extra scanning lines, connect the extra
scanning lines to these common signal pins to avoid any undesirable effects due to crosstalk during the
floating state.
HD44780
Figure 19 Liquid Crystal Display and HD44780 Connections (cont)
COM16
SEG40
COM1
COM8
COM9
SEG1
Example of a 5
8 dot, 8-character
2-line display (1/5 bias, 1/16 duty cycle)
HD44780U
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