BU9729K Datasheet, PDF (10/12 Pages) Rohm – Segment-type LCD driver

Standard ICs
BU9729K
(5) LCD driver power supply
The LCD driver power supply is generated by the BU9729K. V1 = 2 · VC / 3, V2 = VC / 3 is generated internally.
VDD
VLCD
VC
VSS
Fig. 6 Example of power supply connection
(6) LCD drive circuit
The LCD drive circuit is configured of 4 common drivers and 18 segment drivers. When oscillation begins, any effec-
tive common output automatically outputs a selective waveform, while the others output non-selective waveforms.
Segment output automatically outputs drive waveforms, based on the display data and common counter. The com-
mon and segment output waveforms are shown in the following examples.
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