General description

The PCF8534 is a peripheral device which interfaces to almost any Liquid Crystal Display (LCD) with low multiplex rates. It generates the drive signals for any static or multiplexed LCD containing up to four backplanes and up to 60 segments and can easily be cascaded for larger LCD applications. The PCF8534 is compatible with most microprocessors / microcontrollers and communicates via a two-line bidirectional I2C-bus. Communication overheads are minimized using a display RAM with auto-incremented addressing, hardware subaddressing and display memory switching (static and duplex drive modes).

Features

■ Single-chip LCD controller / driver

■ Selectable display bias configuration: static, 1⁄2 or 1⁄3

■ 60 segment drives: up to thirty 8-segment numeric characters; up to sixteen 15-segment alphanumeric characters; or any graphics of up to 240 elements

■ Auto-incremented display data loading across device subaddress boundaries

■ Versatile blinking modes

■ Wide power supply range: from 1.8 to 5.5 V

■ Low power consumption

■ TTL/CMOS compatible

■ May be cascaded for 2 LCD applications

■ Manufactured in silicon gate CMOS process.

■ Selectable backplane drive configuration: static or 2 / 3 / 4 backplane multiplexing

■ Internal LCD bias generation with voltage-follower buffers

■ 60 x 4-bit RAM for display data storage

■ Display memory bank switching in static and duplex drive modes

■ LCD and logic supplies may be separated

■ Wide LCD supply range: from 2.5 V for low threshold LCDs and up to 6.5 V for guest-host LCDs and high threshold (automobile) twisted nematic LCDs

■ 400 kHz I2C-bus interface

■ Compatible with 4-bit, 8-bit or 16-bit microprocessors/microcontrollers

■ No external components