Datasheet

1. General description
The PCF8579 is a low power CMOS
1
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 I
2
C-bus (using the two slave
addresses). The device is optimized for use with the PCF8578 LCD row/column driver.
Together these devices form a general purpose LCD dot matrix driver chip set, capable of
driving displays of up to 40960 dots. The PCF8579 is compatible with most
microcontrollers and communicates via a two-line bidirectional bus (I
2
C-bus). To allow
partial V
DD
shutdown the ESD protection system of the SCL and SDA pins does not use a
diode connected to V
DD
. Communication overhead is minimized by a display RAM with
auto-incremented addressing and display bank switching.
2. Features
n LCD column driver
n Used in conjunction with the PCF8578, this device forms part of a chip set capable of
driving up to 40960 dots
n 40 column outputs
n Selectable multiplex rates; 1:8, 1:16, 1:24 or 1:32
n Externally selectable bias configuration, 5 or 6 levels
n Easily cascadable for large applications (up to 32 devices)
n 1280-bit RAM for display data storage
n Display memory bank switching
n Auto-incremented data loading across hardware subaddress boundaries (with
PCF8578)
n Power-On Reset (POR) blanks display
n Logic voltage supply range 2.5 V to 6 V
n Maximum LCD supply voltage 9 V
n Low power consumption
n I
2
C-bus interface
n Compatible with most microcontrollers
n Optimized pinning for single plane wiring in multiple device applications (with
PCF8578)
n Space saving 56-lead small outline package and 64-pin quad flat pack
PCF8579
LCD column driver for dot matrix graphic displays
Rev. 05 — 11 May 2009 Product data sheet
1. The definition of the abbreviations and acronyms used in this data sheet can be found in Section 15.

Summary of content (41 pages)