HD66750 Datasheet, PDF (18/96 Pages) Hitachi Semiconductor – 128 x 128-dot Graphics LCD Controller/Driver with Four-grayscale Functions

HD66750/1
V-Pin Voltage Follower
A voltage follower for each voltage level (V1 to V5) reduces current consumption by the LCD drive power
supply circuit. No external resistors are required because of the internal bleeder-resistor, which generates
different levels of LCD drive voltage. This internal bleeder-resistor can be software-specified from 1/4 bias
to 1/11 bias, according to the liquid crystal display drive duty value. The voltage followers can be turned
off while multiplexing drive is not being used. For details, see the Power Supply for Liquid Crystal
Display Drive section.
Contrast Adjuster
The contrast adjuster can be used to adjust LCD contrast in 64 steps by varying the LCD drive voltage by
software. This can be used to select an appropriate LCD brightness or to compensate for temperature.
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