1. General description

The PCF8545 is a peripheral device which interfaces to almost any Liquid Crystal Display

(LCD)1 with low multiplex rates. It generates the drive signals for any multiplexed LCD

containing up to eight backplanes, and up to 320 elements. The PCF8545 is compatible

with most microcontrollers and communicates via the two-line bidirectional I2C-bus

(PCF8545A) or a three line unidirectional SPI-bus (PCF8545B). Communication

overheads are minimized using a display RAM with auto-incremented addressing.

For a selection of NXP LCD segment drivers, see Table 40 on page 61.

2. Features and benefits

 Single-chip 320 elements LCD controller and driver

 Wide range for digital power supply: from 1.8 V to 5.5 V

 LCD supply range from 2.5 V up to 5.5 V

 LCD and logic supplies may be separated

 Low power consumption

 Selectable backplane drive configuration: 4, 6, or 8 backplane multiplexing

 Selectable display bias configuration

 320-bit RAM for display data storage

 400 kHz I2C-bus interface (PCF8545A)

 5 MHz SPI-bus interface (PCF8545B)

 Programmable frame frequency in the range of 60 Hz to 300 Hz in steps of 10 Hz;

factory calibrated

 320 segments driven allowing:

 up to 40 7-segment alphanumeric characters

 up to 20 14-segment alphanumeric characters

 any graphics of up to 320 elements

 Manufactured in silicon gate CMOS process

3. Applications

 Industrial and consumer products