PCF8534
Universal LCD driver for low multiplex rates
Rev. 00.05 — 20 February 2007
Preliminary datasheet
1. 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).
2. Features
Single-chip LCD controller / driver
Selectable backplane drive
configuration: static or 2 / 3 / 4
backplane multiplexing
Selectable display bias configuration: Internal LCD bias generation with
static, 1⁄2 or 1⁄3
60 segment drives: up to thirty
voltage-follower buffers
60 x 4-bit RAM for display data storage
8-segment numeric characters; up to
sixteen 15-segment alphanumeric
characters; or any graphics of up to
240 elements
Auto-incremented display data loading Display memory bank switching in static
across device subaddress boundaries
and duplex drive modes
Versatile blinking modes
LCD and logic supplies may be
separated
Wide power supply range: from
Wide LCD supply range: from 2.5 V for
1.8 to 5.5 V
low threshold LCDs and up to 6.5 V for
guest-host LCDs and high threshold
(automobile) twisted nematic LCDs
Low power consumption
400 kHz I2C-bus interface
TTL/CMOS compatible
Compatible with 4-bit, 8-bit or 16-bit
microprocessors/microcontrollers
May be cascaded for 2 LCD applications No external components
Manufactured in silicon gate CMOS
process.