General description

The PCF8579 is a low power CMOS1 LCD column driver, designed to drive dot matrix graphic displays at multiplex rates of 1:8, 1:16, 1:24 or 1:32. The device has 40 outputs and can drive 32 × 40 dots in a 32 row multiplexed LCD. Up to 16 PCF8579s can be cascaded and up to 32 devices may be used on the same I2C-bus (using the two slave addresses). The device is optimized for use with the PCF8578 LCD row/column driver.

Features

■ LCD column driver

■ Used in conjunction with the PCF8578, this device forms part of a chip set capable of driving up to 40960 dots

■ 40 column outputs

■ Selectable multiplex rates; 1:8, 1:16, 1:24 or 1:32

■ Externally selectable bias configuration, 5 or 6 levels

■ Easily cascadable for large applications (up to 32 devices)

■ 1280-bit RAM for display data storage

■ Display memory bank switching

■ Auto-incremented data loading across hardware subaddress boundaries (with PCF8578)

■ Power-On Reset (POR) blanks display

■ Logic voltage supply range 2.5 V to 6 V

■ Maximum LCD supply voltage 9 V

■ Low power consumption

■ I2C-bus interface

■ Compatible with most microcontrollers

■ Optimized pinning for single plane wiring in multiple device applications (with PCF8578)

■ Space saving 56-lead small outline package and 64-pin quad flat pack

Applications

■ Automotive information systems

■ Telecommunication systems

■ Point-of-sale terminals

■ Industrial computer terminals

■ Instrumentation