Direct LCD Drive

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Direct LCD drive

Each LCD segment is connected to an I/O “Segment” and to one backplane common to all the

segments. A display using S segments is driven with S+1 MCU output lines. The backplane is

When selecting a segment “ON”, a signal with opposite polarity to “COM” is sent to the corre-

sponding “Segment” pin. When the non-inverted signal “COM” is sent to the “Segment” pin, the

segment is “OFF”. Using an MCU the I/O operate in output mode either at the logic levels 0 or

1.

Figure 2. LCD signals for direct drive