SA8807A

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3.

LCD Display

The SA8807A LCD driver is capable of driving a 3 or 4 backplane, 12 digit (7

segment) display, plus decimal points.

In the case of a 4 back plane display, typically the most significant digit is addressed

by columns VS[22] and VS[23] and the least significant digit, by VS[0] and VS[1].

The display segments addressed via the column outputs are given in a typical

configuration below:

The data in memory is constantly being displayed on the liquid crystal display. New

data is displayed as soon as it is latched into memory.

A segment is switched on when the corresponding difference between backplane

VR[ ] and segment VS[ ] outputs is V

The voltage is alternated to avoid a DC voltage on the LCD (See Diagram 2).

The backplane multiplex rate is determined by the clock/oscillator frequency on the

CLK input.